4-carboxamido-isoindolinone derivatives as selective PARP-1 inhibitors

ABSTRACT

There are provided substituted 4-carboxamido-isoindolinone derivatives which selectively inhibit the activity of poly (ADP-ribose) polymerase PARP-I with respect to poly (ADP-ribose) polymerase P ARP-2. The compounds of this invention are therefore useful in treating diseases such as cancer, cardiovascular diseases, central nervous system injury and different forms of in-flammation. The present invention also provides methods for preparing these compounds, pharmaceutical compositions comprising these compounds, and methods of treating diseases utilizing pharmaceutical compositions comprising these compounds.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of co-pending application havingU.S. Ser. No. 14/438,410, filed on Apr. 24, 2015, which is a 371 ofInternational Application having Serial No. PCT/EP2013/072165, filed onOct. 23, 2013, which claims benefit of European Patent Application No.12190130.0, filed on Oct. 26, 2012, the contents of all of which areincorporated herein by reference.

The present invention provides novel substituted4-carboxamido-isoindolinone derivatives which proved to be potent andselective poly (ADP-ribose) polymerase-1 (PARP-1) inhibitors withrespect to poly (ADP-ribose) polymerase-2 (PARP-2) and are thus usefulin the therapy of cancer, cardiovascular diseases, nervous system injuryand inflammation. The present invention also provides methods forpreparing these compounds, pharmaceutical compositions comprising thesecompounds, and methods of treating diseases utilizing pharmaceuticalcompositions comprising these compounds.

Poly (ADP-ribose) polymerases belong to a family of 18 members thatcatalyze the addition of ADP-ribose units to DNA or different acceptorproteins, which affect cellular processes as diverse as replication,transcription, differentiation, gene regulation, protein degradation andspindle maintenance. PARP-1 and PARP-2 are the only enzymes among thePARPs that are activated by DNA damage and are involved in DNA repair.

PARP-1 is a nuclear protein consisting of three domains: the N-terminalDNA-binding domain containing two zinc fingers, the auto modificationdomain, and the C-terminal catalytic domain. PARP-1 binds through thezinc-finger domain to DNA single strand breaks (SSB), cleaves NAD⁺, andattaches multiple ADP-ribose units to target proteins such as histonesand various DNA repair enzymes. This results in a highly negativelycharged target, which in turn leads to the unwinding and repair of thedamaged DNA through the base excision repair pathway. In knock out mousemodels, deletion of PARP-1 impairs DNA repair but it is not embryoniclethal. Double knock out PARP-1 and PARP-2 mice instead die during earlyembryogenesis, suggesting that the two enzymes display not completelyoverlapping functions. Enhanced PARP-1 expression and/or activity havebeen shown in different tumor cell lines, including malignant lymphomas,hepatocellular carcinoma, cervical carcinoma, colorectal carcinoma,leukemia. This may allow tumor cells to withstand genotoxic stress andincrease their resistance to DNA-damaging agents. As a consequence,inhibition of PARP-1 through small molecules has been shown to sensitizetumor cells to cytotoxic therapy (e.g. temozolomide, platinums,topoisomerase inhibitors and radiation). A significant window seems toexist between the ability of a PARP inhibitor to potentiate therapeuticbenefits and undesirable side effects. Whereas the therapeutic use ofPARP inhibitors in combination with DNA damaging agents is not novel,the use of these agents as monotherapy, in particular tumor geneticbackgrounds deficient in the homologous recombination DNA repair,represents a new approach. Individuals with heterozygous germ linemutations in either the BRCA-1 or BRCA-2 homologous recombination repairgenes exhibit high life time risks of developing breast and othercancers. Tumors arising in mutation carriers have generally lost thewild type allele and do not express functional BRCA-1 and BRCA-2proteins.

Therefore, loss of these two proteins leads to a tumor-specificdysfunction in the repair of double strand breaks by homologousrecombination. It is known that when PARP-1 is inhibited, base excisionrepair is reduced and single strand breaks that are generated during thenormal cell cycle persist. It has also been established that replicationforks that encounter an unrepaired break can form double strand breakswhich are normally repaired by homologous recombination. Tumor cellsthat are deficient in homologous recombination repair such as BRCA-1 andBRCA-2 mutants are therefore highly sensitive to PARP inhibitioncompared with wild-type cells. This is in line with the concept ofsynthetic lethality, in which the two pathway defects alone areinnocuous but combined become lethal: PARP inhibitors may be moreeffective in patients with tumors with specific DNA repair defectswithout affecting normal heterozygous tissues. Putative patientpopulation includes, besides BRCA mutants that represent the majority ofhereditary breast and ovarian cancer, also a substantial fraction ofsporadic cancers with defects in homologous recombination repair, aphenomenon termed “BRCAness”. For example, methylation of the promotersof the BRCA-1 or FANCF genes and amplification of the EMSY gene, whichencodes a BRCA-2 interacting protein. By extending the rational ofsynthetic lethality of PARP and BRCA-1 and BRCA-2, it is likely thatdeficiencies in any gene that is not redundant in double strand breakrepair should be sensitive to PARP inhibition. For example, ATMdeficiency, found in patients with T-cell prolymphocytic leukemia andB-cell chronic lymphocytic leukemia and breast cancer and CHK2 germ linemutations identified in sarcoma, breast cancer, ovarian cancer and braintumors, have also been shown to be synthetically lethal in combinationwith PARP deficiency as well as deficiencies in other known HR pathwayproteins (including RAD51, DSS1, RAD54, RPA1, NBS1, ATR, CHK1, CHK2,FANCD2, FANCA, FANCC and pTEN). Mutations in FANCC and FANCG have beenshown in pancreatic cancer. Methylation of FANCF promoter has been foundin ovarian, breast, cervical, lung carcinomas. The first clinicalevidence that BRCA-mutated cancer may be sensitive to PARP inhibitormonotherapy comes from the phase I trial of the oral, small moleculePARP inhibitor Olaparib. In an enriched phase I population for BRCAmutation carriers, an objective response rate of 47% were observed in 19patients with BRCA mutations and breast, ovarian and prostate cancer.Other PARP inhibitors, such as Rucaparib and Veliparib are currentlyknown to be in phase II clinical trials in combination as well as singleagent. Early indications are that these therapies show low toxicity assingle agent. Anyway compounds with high selectivity on PARP-1 areexpected to show even less toxicity in view of a chronic treatmentschedule or in combination.

PARP-1 has also been implicated in angiogenesis. In particular, PARP-1inhibition seems to result in decreased accumulation of thetranscription hypoxia-inducible factor 1α, an important regulator oftumor cell adaptation to hypoxia.

Pro-inflammatory stimuli trigger the release of pro-inflammatorymediators that induce the production of peroxynitrate and hydroxylradicals, which in turn yield to DNA single strand breakage withconsequent activation of PARP-1. Over activation of PARP-1 results indepletion of NAD+ and energy stores, culminating in cell dysfunction andnecrosis. This cellular suicide mechanism has been implicated in thepathomechanism of stroke, myocardial ischemia, diabetes,diabetes-associated cardiovascular dysfunction, shock, traumatic centralnervous system injury, arthritis, colitis, allergic encephalomyelitisand various other forms of inflammation. Of special interest is theenhancement by PARP-1 of nuclear factor kB-mediated transcription, whichplays a central role in the expression of inflammatory cytokines,chemokines and inflammatory mediators.

WO 2007/047646 in the name of Janssen Pharmaceutica describessubstituted dihydro-isoindolones useful for treating kinase disorders;Wender et al. claim in U.S. Pat. No. 7,232,842 isoindolone analogs askinase inhibitors. The Patent Application US 2008/0108659 of Gandhi etal. describes 3-oxo-2,3-dihydro-1H-isoindoles as poly (ADP-ribose)polymerase inhibitors, also reported in: Bioorg. Med. Chem. Left., 2010,20, 1023-1026. WO 2011/006794 and WO 2011/006803, both in the name ofNerviano Medical Sciences, describe3-oxo-2,3-dihydro-1H-isoindole-4-carboxamides as selective PARP-1inhibitors.

The present invention provides novel substituted4-carboxamido-isoindolinone derivatives which proved to be potent andselective PARP-1 inhibitors with respect to PARP-2 and are thus usefulin the therapy of cancer, cardiovascular diseases, nervous system injuryand inflammation.

The present invention also provides method for preparing thesecompounds, pharmaceutical compositions comprising these compounds, andmethods of treating diseases utilizing pharmaceutical compositionscomprising these compounds.

Accordingly, a first object of the present invention is to provide acompound of formula (I):

wherein:

R is hydrogen or fluorine; and

n, m, R1 and R2 have the following meanings:

a) n is 0 and m is 0, 1, 2 or 3;

R1 is 3- to 6-membered cycloalkyl or 4- to 6-membered heterocycyl; and

R2 is a 3-, 5- or 6-membered cycloalkyl, 4- to 6-membered heterocyclyl,aryl or heteroaryl;

or

b) n is 1 and m is 0;

R1 is 3- to 6-membered cycloalkyl or aryl, each of which optionallyfurther substituted with one or more linear or branched (C₁-C₆)-alkyl;and

R2 is null, 3- to 6-membered cycloalkyl, 4- to 6-membered heterocyclyl,aryl or heteroaryl, each of which optionally further substituted withone or more linear or branched (C₁-C₆)-alkyl;

or

c) n is 2 or 3, and m is 0;

R1 is a 3- to 6-membered cycloalkyl, 4- to 6-membered heterocyclyl, arylor heteroaryl, each of which optionally further substituted with one ormore linear or branched (C₁-C₆)-alkyl; and

R2 is null, 3- to 6-membered cycloalkyl, 4- to 6-membered heterocyclyl,aryl or heteroaryl, each of which optionally further substituted withone or more linear or branched (C₁-C₆)-alkyl;

or

d) n and m are each independently 1, 2 or 3;

R1 and R2 are each independently 3- to 6-membered cycloalkyl, 4- to6-membered heterocyclyl, aryl or heteroaryl;

or a pharmaceutically acceptable salt thereof.

The compounds of formula (I) as defined above are potent and selectivePARP-1 inhibitors with respect to PARP-2 and are thus useful in cancer,cardiovascular diseases, nervous system injury and inflammation therapy.

The present invention also provides methods of synthesizing substituted4-carboxamido-isoindolinone derivatives of formula (I) as defined above,through a process consisting of standard synthetic transformations.

The present invention also provides a method for treating diseasesmediated by PARP-1 protein which comprises administering to a mammal inneed thereof, preferably a human, an effective amount of a compound offormula (I), as defined above.

A preferred method of the present invention is to treat a diseasemediated by PARP-1 protein selected from the group consisting of cancer,cardiovascular diseases, nervous system injury and inflammation.

Another preferred method of the present invention is to treat specifictypes of cancer including, but not limited to: carcinomas, such asbladder, breast, colon, kidney, liver, lung, including small cell lungcancer, esophagus, gall-bladder, ovary, pancreas, stomach, cervix,thyroid, prostate, and skin, including squamous cell carcinoma:hematopoietic tumors of lymphoid lineage, including leukemia, acutelymphocytic leukemia, acute lymphoblastic leukemia, B-cell lymphoma,T-cell-lymphoma, Hodgkin's lymphoma, non-Hodgkin's lymphoma, hairy celllymphoma and Burkitts lymphoma; hematopoietic tumors of myeloid lineage,including acute and chronic myelogenous leukemias, myelodysplasticsyndrome and promyelocytic leukemia: tumors of mesenchymal origin,including fibrosarcoma, Ewing's sarcoma and rhabdomyosarcoma; tumors ofthe central and peripheral nervous system, including astrocytoma,neuroblastoma, glioma and schwannomas; and other tumors, includingmelanoma, seminoma, teratocarcinoma, osteosarcoma, xerodermapigmentosum, keratoxanthoma, thyroid follicular cancer and Kaposi'ssarcoma.

In addition, the method of the present invention also provides tumorangiogenesis and metastasis inhibition. Another preferred method of thepresent invention is to treat specific types of cardiovascular diseasesincluding, but not limited to, myocardial reperfusion injury,cardiomyopathy, diabetic cardiovascular dysfunction.

Another preferred method of the present invention is to treat specifictypes of nervous system injury including but not limited to: stroke,brain injury and neurodegenerative disorders.

Another preferred method of the present invention is to treat specifictypes of inflammation diseases including, but not limited to, colitis,arthritis and uveitis.

The present invention also provides an in vitro method for selectivelyinhibiting PARP-1 protein activity which comprises contacting the saidprotein with an effective amount of a compound of formula (I), asdefined above.

The present invention further provides a method for treating diseasescomprising a compound of formula (I), as defined above, in combinationwith radiation therapy or chemotherapy regimen for simultaneous,separate or sequential use in anticancer therapy.

The present invention also provides a pharmaceutical compositioncomprising a therapeutically effective amount of a compound of formula(I) or a pharmaceutically acceptable salt thereof, as defined above, andat least one pharmaceutically acceptable excipient, carrier or diluent.

In addition to a compound of formula (I), the pharmaceutical compositionof the present invention may further comprise one or morechemotherapeutic—e.g. cytostatic or cytotoxic—agents, antibiotic-typeagents, alkylating agents, antimetabolite agents, hormonal agents,immunological agents, interferon-type agents, cyclooxygenase inhibitors(e.g. COX-2 inhibitors), matrix metalloproteinases inhibitors,telomerase inhibitors, tyrosine kinase inhibitors, anti-growth factorreceptor agents, anti-HER agents, anti-EGFR agents, anti-angiogenesisagents (e.g. angiogenesis inhibitors), famesyl transferase inhibitors,ras-raf signal transduction pathway inhibitors, cell cycle inhibitors,other cdks inhibitors, tubulin binding agents, topoisomerase Iinhibitors, topoisomerase II inhibitors, and the like. Preferably, thechemotherapeutic agent is an alkylating agent Even more preferably, thealkylating agent is temozolomide.

Additionally, the invention provides a product comprising a compound offormula (I) or a pharmaceutically acceptable salt thereof, as definedabove, and one or more chemotherapeutic agents, as a combinedpreparation for simultaneous, separate or sequential use in anticancertherapy. Preferably, the chemotherapeutic agent is an alkylating agent.Even more preferably, the alkylating agent is temozolomide.

Moreover, the invention provides a compound of formula (I) or apharmaceutically acceptable salt thereof, as defined above, for use as amedicament, preferably as a medicament with anticancer activity.

In yet another aspect, the invention provides a compound of formula (I)or a pharmaceutically acceptable salt thereof, as defined above, for usein a method of treating cancer.

Finally, the invention provides the use of a compound of formula (I) ora pharmaceutically acceptable salt thereof, as defined above, in themanufacture of a medicament with anticancer activity.

The compounds of formula (I) may have one or more asymmetric centers,and may therefore exist as individual optical isomers or racemicmixtures or diastereoisomers. Accordingly, al the possible isomers, andtheir mixtures of the compounds of formula (I) are within the scope ofthe present invention. As stated above, salts of the compounds offormula (I) are also within the scope of the present invention.

Unless otherwise specified, when referring to the compounds of formula(I) per se as well as to any pharmaceutical composition thereof or toany therapeutic treatment comprising them, the present inventionincludes all of the isomers, tautomers, hydrates, solvates, N-oxides andpharmaceutically acceptable salts of the compounds of this invention.

If a chiral center or another form of an isomeric center is present in acompound of the present invention, all forms of such isomer or isomers,including enantiomers and diastereoisomers, are intended to be coveredherein. Compounds containing a chiral center may be used as a racemicmixture, an enantiomerically enriched mixture, or the racemic mixturemay be separated using well-known techniques and an individualenantiomer may be used alone. In cases in which compounds haveunsaturated carbon-carbon double bonds, both the cis (Z) and trans (E)isomers are within the scope of this invention.

In cases wherein compounds may exist in tautomeric forms, such asketo-enol tautomers, each tautomeric form is contemplated as beingincluded within this invention whether existing in equilibrium orpredominantly in one form.

With the term “halogen” we intend a fluorine, chlorine, bromine oriodine atom.

With the term “linear or branched (C₁-C₆)-alkyl”, we intend any of thegroups such as, for instance, methyl, ethyl, n-propyl, isopropyl,n-butyl, isobutyl, tert-butyl, sec-butyl, n-pentyl, n-hexyl, and thelike.

With the term “3- to 6-membered cycloalkyl” we intend, unless otherwiseprovided, a 3- to 6-membered all-carbon monocylic ring, which maycontain one or more double bonds but does not have a completelyconjugated π-electron system. Examples of cycloalkyl groups, withoutlimitation, are cyclopropyl, cyclobutyl, cyclopentyl, cyclopentenyl,cyclohexyl, cyclohexenyl and cyclohexadienyl.

With the term “4- to 6-membered heterocyclyl” we intend a 4- to6-membered, saturated or partially unsaturated carbocyclic ring whereone or more carbon atoms are replaced by heteroatoms such as nitrogen,oxygen and sulfur the heterocyclyl ring can be optionally further fusedor linked to aromatic and non-aromatic carbocyclic and heterocyclicrings. Non limiting examples of heterocyclyl groups are, for instance,pyranyl, pyrrolidinyl, pyrrolinyl, imidazolinyl, imidazolidinyl,pyrazolidinyl, pyrazolinyl, thiazolinyl, thiazolidinyl, dihydrofuranyl,tetrahydrofuranyl, 1,3-dioxolanyl, piperidinyl, piperazinyl, morpholinyland the like.

The term “aryl” refers to a mono-, bi- or poly-carbocyclic hydrocarbonwith from 1 to 4 ring systems, optionally further fused or linked toeach other by single bonds, wherein at least one of the carbocyclicrings is “aromatic”, wherein the term “aromatic” refers to completelyconjugated n-electron bond system. Non limiting examples of such arylgroups are phenyl, α- or β-naphthyl or biphenyl groups.

The term “heteroaryl” refers to aromatic heterocyclic rings, typically5- to 8-membered heterocycles with from 1 to 3 heteroatoms selectedamong N, O or S; the heteroaryl ring can be optionally further fused orlinked to aromatic and non-aromatic carbocyclic and heterocyclic rings.Not limiting examples of such heteroaryl groups are, for instance,pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, indolyl, imidazolyl,thiazolyl, isothiazolyl, pyrrolyl, phenyl-pyrrolyl, furyl, phenyl-furyl,oxazolyl, isoxazolyl, pyrazolyl, thienyl, benzothienyl, isoindolinyl,benzoimidazolyl, indazolyl, quinolinyl, isoquinolinyl, 1,2,3-triazolyl,1-phenyl-1,2,3-triazolyl, 2,3-dihydroindolyl, 2,3-dihydrobenzofuranyl,2,3-dihydrobenzothiophenyl; benzopyranyl, 2,3-dihydrobenzoxazinyl,2,3-dihydroquinoxalinyl and the like.

According to the present invention and unless otherwise provided, whenany of the above mentioned groups is optionally substituted, it may besubstituted in any of its free position by one or more linear orbranched (C₁-C₆) alkyl groups.

The term “pharmaceutically acceptable salt” of compounds of formula (I)refers to those salts that retain the biological effectiveness andproperties of the parent compound, therefore pharmaceutically acceptablesalts of the compounds of formula (I) include the acid addition saltswith inorganic or organic acids, e.g., nitric, hydrochloric,hydrobromic, sulfuric, perchloric, phosphoric, acetic, trifluoroacetic,propionic, glycolic, (D) or (L) lactic, oxalic, ascorbic, fumaric,malonic, malic, maleic, tartaric, citric, benzoic, cinnamic, mandelic,methanesulphonic, ethanesulfonic, p-toluenesulfonic, isethionic,succinic and salicylic acid.

Pharmaceutically acceptable salts of the compounds of formula (I) alsoinclude the salts with inorganic or organic bases, e.g., alkali oralkaline-earth metals, especially sodium, potassium, calcium, ammoniumor magnesium hydroxides, carbonates or bicarbonates, and acyclic orcyclic amines, preferably methylamine, ethylamine, diethylamine,triethylamine, piperidine and the like.

In a first preferred embodiment, the present invention providescompounds of formula (I) as defined above characterized in that

R is hydrogen or fluorine; and

n, m, R1 and R2 have the following meanings:

a) n is 0 and m is 0 or 1;

R1 is a 6-membered heterocyclyl; and

R2 is a 3- or 6-membered cycloalkyl, 6-membered heterocyclyl, aryl orheteroaryl;

or

b) n is and m is 0;

R1 is aryl, optionally further substituted with one or more linear orbranched (C₁-C₆)-alkyl; and

R2 is null;

or

c) n is 2 or 3, and m is 0;

R1 is a 6-membered heterocyclyl, aryl or heteroaryl, each of whichoptionally further substituted with one or more linear or branched(C₁-C₆)-alkyl; and

R2 is null, a 6-membered heterocyclyl or aryl;

or

d) n is 2 or 3, and m is 1;

R1 is a 6-membered heterocyclyl; and

R2 is aryl;

or a pharmaceutically acceptable salt thereof.

In a more preferred embodiment, the present invention provides compoundsof formula (I) as defined above characterized in that

R is hydrogen or fluorine; and

n, m, R1 and R2 have the following meanings:

a) n is 0 and m is 0 or 1;

R1 is a 6-membered heterocyclyl; and

R2 is a 3- or 6-membered cycloalkyl, 6-membered heterocyclyl, aryl orheteroaryl;

or

c) n is 2 or 3, and m is 0;

R1 is a 6-membered heterocycyl, aryl or heteroaryl, each of whichoptionally further substituted with one or more linear or branched(C₁-C₆)-alkyl; and

R2 is null, a 6-membered heterocyclyl or aryl;

or a pharmaceutically acceptable salt thereof.

Even more preferably, the present invention provides compounds offormula (I) as defined above characterized in that

R is hydrogen or fluorine; and

n, m, R1 and R2 have the following meanings:

a) n is 0 and m is 0 or 1;

R1 is a 6-membered heterocyclyl; and

R2 is a 3- or 6-membered cycloalkyl, 6-membered heterocyclyl, aryl orheteroaryl;

or a pharmaceutically acceptable salt thereof.

Most preferably, the present invention provides compounds of formula (I)as defined above characterized in that

R is hydrogen or fluorine; and

n, m, R1 and R2 have the following meanings:

a) n is 0 and m is 0 or 1;

when m is 0, R1 is a piperidine ring and R2 is a cyclohexyl ring;

when m is 1, R1 is a piperidine ring and R2 is a pyridine ring;

or a pharmaceutically acceptable salt thereof.

Specific preferred compounds (cpd) of the present invention are listedbelow.

-   1. 2-benzyl-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic acid amide;-   2. 3-oxo-2-phenethyl-2,3-dihydro-1H-isoindole-4-carboxylic acid    amide;-   3.    2-[2-(3,4-dihydro-1H-isoquinolin-2-yl)-ethyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   4.    3-oxo-2-(2-piperidin-1-yl-ethyl)-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   5.    2-(2-morpholin-4-yl-ethyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   6.    2-(3-morpholin-4-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   7.    2-[2-(3,4-dihydro-2H-quinolin-1-yl-ethyl]-3-oxo-2,3-dihydro-1-isoindole-4-carboxylic    acid amide;-   8.    3-oxo-2-(1-pyridin-ylmethyl-piperidin-1-yl)-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   9.    3-oxo-2-(1-thiophen-2-ylmethyl-piperidin-4-yl)-2,3-dihydro-1H-isoindole-4-carboxyl    is acid amide;-   10.    3-oxo-2-(1-pyridin-3-ylmethyl-piperidin-4-yl)-2,3-dihydro-1H-isoindole-carboxylic    acid amide;-   11.    2-(1-cyclohexyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-caboxyl    is acid amide;-   12.    2-(1-furan-ylmethyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   13.    3-ox-2-(1-thiophen-3-ylmethyl-piperidin-4-yl)-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   14.    2-(1-furan-3-ylmethyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   15.    3-oxo-2-(1-pyridin-2-ylmethyl-piperidin-4-yl)-2,3-dihydro-1H-isoindole-4-carboxyl    acid amide;-   16.    3-oxo-2-[1-(1H-pyrrol-2-ylmethyl)-piperidin-4-yl]-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   17. 3-oxo-2-(3-phenyl-propyl)-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   18.    3-oxo-2-(2-pyridin-2-yl-ethyl)-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   19.    2-[3-(3,4-dihydro-1H-isoquinolin-2-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   20.    2-[3-(3,4-dihydro-2H-quinolin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   21.    2-[3-(4-methyl-piperazin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   22.    3-oxo-2-[3-(4-phenyl-piperazin-1-yl-propyl]-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   23.    6-furo-2-(3-morpholin-4-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   24.    2-(1-cyclopropylmethyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   25.    3-oxo-2-(3-piperidin-1-yl-propyl)-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   26.    2-(3-[1,4′]bipiperidinyl-1′-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   27.    2-[3-(2,6-dimethyl-piperidin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   28.    3-oxo-2-[1-(tetrahydro-pyran-4)piperidin-4-yl]-2,3-dihydro-1H-isoindole-4-carboxylicacid    amide;-   29.    2-(1-cyclohexyl-piperidin-4-yl)-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   30.    2-(1-benzyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   31.    2-[2-(1-benzyl-piperidin-yl)-ethyl]-3-oxo-2,3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   32.    2-[3-(4-benzyl-piperidin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   33.    2-[1-(4,4-dimethyl-cyclohexyl)-piperidin-4-yl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   34.    2-[1-(4,4-dimethyl-cyclohexyl)-piperidin-4-]-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   35.    6-fluoro-3-oxo-2-(1-spiro[2.5]oct-6-yl-piperidin-4-yl)-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;-   36.    3-oxo-2-(1-spiro[2.5]oct-6-yl-piperidin-4-yl)-2,3-dihydro-1H-isoindole-4-carboxylic    acid amide;

or a pharmaceutically acceptable salt thereof.

The present invention also provides processes for the preparation ofcompounds of formula (I) as defined above.

Accordingly, a process of the present invention comprises one of thefollowing sequences of steps:

SEQUENCE A (when R is Fluorine, Scheme 1):

either

Step a) halogenating 4-fluoro-2-methyl-phenylamine (XI):

Step b) cyano-de-aminating the resultant compound of formula (X):

wherein Hal is halogen such as Cl, Br, and I;

Step c) hydrolyzing the resultant compound of formula (IX):

wherein Hal is as defined above and

Step d) hydrolyzing the resultant compound of formula (VIII):

wherein Hal is as defined above;

or

Step e) halogenating 4-fluoro-2-methy-benzoic acid (XII):

Then:

Step f) esterifying the compound of formula (VII) obtained in step d) ore)

wherein Hal is as defined above;

Step g) cyano-de-halogenating the resultant compound of formula (VI):

wherein T is a (C₁-C₆)-alkyl or an aryl-(C₁-C₆)-alkyl and Hal is asdefined above;

Step h) cyclizing the resultant compound of formula (V):

wherein T is as defined above, by reaction with a suitable amine offormula (XIII)X—R1-[CH₂]_(n)—NH₂  (XIII)

wherein R1 and n are as defined above, and X is either R2-[CH₂]_(m)—,wherein R2 and m are as defined above, or a suitable nitrogen protectivegroup, when R1 is a nitrogen containing heterocyclyl;

Step c′) hydrolyzing the resultant compound of formula (IV):

wherein R1, n and X are as defined above, so as to obtain

a compound of formula (I), as defined above, when X is R2-[CH₂]_(m)—,wherein R2 and m are as defined above; or

a compound of formula (III), when R1 is a nitrogen containingheterocyclyl and X is a suitable nitrogen protective group,

wherein n is as defined above, R1 is a nitrogen containing heterocyclyland X is a suitable nitrogen protective group;

Step i) deprotecting the compound of formula (III), as defined above, soas to obtain either

a compound of formula (I), as defined above, or

a compound of formula (II):

wherein R1 and n are as defined above;

Step l) alkylating the resultant compound of formula (II), as definedabove, with a suitable alkylating agent of formula (XIV)R2-[CH₂]_(m-1)—Y  (XIV)

wherein Y is either a formyl group or, when m=1, an oxygen atom linkedto R2 through a double bond (═O), so as to obtain a compound of formula(I).

SEQUENCE B (when R is Hydrogen, Scheme 2):

Step m) performing a reductive amination on furan-2-carbaldehyde (XV):

with a suitable amine of formula (XIII)X—R1-[CH₂]_(n)—NH₂  (XIII)

wherein R1 and n are as defined above, and X is either R2-[CH₂]_(m)—,wherein R2 and m are as defined above, or a suitable nitrogen protectivegroup, when R1 is a nitrogen containing heterocyclyl;

Step n) performing a Diels-Alder reaction on the resultant compound offormula (XVI):

wherein R1, n and X are as defined above;

Step o) aromatizing the resultant compound of formula (XVII):

wherein R1, n and X are as defined above;

Step p) amidating the resultant compound of formula (XVIII)

wherein R1, n and X are as defined above, so as to obtain

a compound of formula (I), as defined above, when X is R2-[CH₂]_(m)—,wherein R2 and m are as defined above; or

a compound of formula (XX), when R1 is a nitrogen containingheterocyclyl and X is a suitable nitrogen protective group,

wherein n is as defined above, R1 is a nitrogen containing heterocyclyland X is a suitable nitrogen protective group;

Step i′) deprotecting a compound of formula (XX) as defined above;

Step i′) alkylating the resultant compound of formula (XXI):

wherein R1 and n are as defined above, with a suitable alkylating agentof formula (XIV)R2-[CH₂]_(m-1)—Y  (XIV)

wherein Y is either a formyl group or, when m=1, an oxygen atom linkedto R2 through a double bond (═O), so as to obtain a compound of formula(I), as defined above.

In case, during Step o, the compound resulting from aromatization of acompound of formula (XVII) is a compound of formula (XIX), i.e. when Xis a labile nitrogen protective group, the following Step q isperformed:

Step q) installing a suitable nitrogen protective group on the resultantcompound of formula (XIX):

wherein R1 and n are as defined above, so as to obtain a compound offormula (XVIII), wherein R1 and n are as defined above and X is asuitable nitrogen protective group, which is then subjected to thesequence of reactions p), i′) and l′) above described so as to obtain acompound of formula (I) as above defined.

If necessary or wanted, the processes above described comprisesconverting a compound of formula (I) into a different compound offormula (I) by known chemical reactions; and/or, if desired, convertinga compound of formula (I) into a pharmaceutically acceptable saltthereof or converting a salt into a free compound of formula (I).

Such known chemical reactions for possible conversions of compounds intodifferent compounds comprise for instance a reductive amination (Cv1).

All the above processes are analogy processes which can be carried outaccording to well known methods and under suitable conditions known inthe art.

The synthesis of a compound of formula (I), according to the syntheticprocesses described above, can be carried out in a stepwise manner,whereby each intermediate is isolated and purified by standardpurification techniques, like, for example, column chromatography,before carrying out the subsequent reaction. Alternatively, two or moresteps of the synthetic sequence can be carried out in a so-carried“one-pot” procedure, as known in the art, whereby only the compoundresulting from the two or more steps is isolated and purified.

Schemes 1-2 below show the preparation of a compound of formula (I) asdefined above.

According to step a), a compound of formula (X) can be obtained byhalogenating 4-fluoro-2-methyl-phenylamine (XI) in a variety of ways andexperimental conditions known in the art. Preferably this reaction isconducted in the presence of N-bromosuccinimide, N-iodosuccinimmide,N-chborosuccinimide, bromine, iodine, hydrobromic acid/hydrogenperoxide, in a suitable solvent, such as acetonitrile,N,N-dimethylformamide, dioxane, dimethylsulfoxide, acetic acid or water,at a temperature ranging from about room temperature to reflux and for aperiod of time varying from about 1 h to about 96 h.

According to step b), a compound of formula (IX) can be obtained by atwo-steps reaction sequence from a compound of formula (X) in a varietyof ways and experimental conditions known in the art. First step ispreferably conducted in the presence of sodium nitrite/hydrochloric acidor tert-butylnitrite in a suitable solvent, such as tetrahydrofuran,dimethoxyethane, dimethylsulfoxide, acetic acid or water, at atemperature ranging from about −20° C. to room temperature and for aperiod of time varying from 10 min to about 24 h. Second step ispreferably carried out in the presence of sodium, copper or potassiumcyanide, often in the presence of an additive such as copper orpotassium chloride, in a suitable solvent, such as tetrahydrofuran,dimethoxyethane, dimethylsulfoxide, acetic acid, toluene or water, at atemperature ranging from about −20° C. to reflux and for a period oftime ranging from about 10 min to about 96 h.

According to step c), the hydrolysis of a compound of formula (IX) to agive a compound of formula (VIII) can be carried out in a variety ofways, according to conventional methods for transforming a cyano groupto amide. Preferably this reaction is carried out in a suitable solventsuch as, for instance, methanol, ethanol, butanol, 1,4-dioxane, toluene,water, or a mixture thereof, in the presence of a suitable acid or base,such as, for instance, sulfuric acid, methanesulfonic acid, hydrochloricacid, trifluoroacetic acid, sodium hydroxide, sodium carbonate, or asuitable reagent such as hydrogen peroxide, sodium perborate orindium(III) salts in the presence of acetaldoxime. Typically, thereaction is carried out at a temperature ranging from room temperatureto reflux and for a time varying from about 1 h to about 96 h.

According to step d), a compound of formula (VIII) can be transformedinto a compound of formula (VII) according to conventional methods.Preferably the reaction is carried out in the presence of water bytreatment with a base such as potassium or sodium carbonate, potassiumor sodium hydroxide, in a suitable solvent such as, for instance,methanol or ethanol, at a temperature ranging from room temperature toreflux, for a time ranging from about 30 min to about 96 h.Alternatively this reaction can be conducted in the presence of sodiumnitrite/acetic acid, sulfuric acid, phosphoric acid, at a temperatureranging from room temperature to reflux and for a time varying fromabout 1 h to about 96 h.

According to step e), the halogenation of 4-fluoro-2-methyl-benzoic acid(XII) into a compound of formula (VII) can be carried out in a varietyof ways, according to conventional methods for halogenation reactions.Preferably, this reaction is carried out with tetrabutylammonium bromideand/or iodine in the presence of phenyliodine(III) bis(trifluoracetate)or phenyliodo(III) diacetate as halogen source in a suitable solventsuch as, for instance, N,N-dimethylformamide or dichloroethane, at atemperature ranging from room temperature to reflux and for a timevarying from about 1 h to about 48 h. The catalyst is usually a metal,most often a palladium derivative such as, for instance, palladium(II)chloride or palladium(II) acetate.

According to step f), a compound of formula (VII) can be transformedinto a compound of formula (VI) according to conventional methods.Preferably the reaction is carried out in the presence of hydrochloricacid, sulfuric acid or acetic acid by using as a solvent methanol,ethanol, water, or a mixture thereof, at a temperature ranging from roomtemperature to reflux and for a time varying from about 1 h to about 96h. Alternatively, this reaction can be conducted with alkyl iodide,bromide or toluensulfonate in the presence of a suitable base, such assodium or potassium carbonate, and sodium, lithium or potassiumhydroxide, at a temperature ranging from room temperature to reflux andfor a time varying from about 1 h to about 96 h.

According to step g), the transformation of a compound of formula (VI)into a compound of formula (V) can be carried out in a variety of ways,according to conventional methods for cyanation reactions. Preferably,this reaction is carried out in the presence of copper(I) cyanide orpotassium hexacyanoferrate(III) as cyano source in a suitable solventsuch as, for instance, methanol, ethanol, tetrahydrofuran, 1,4-dioxane,toluene, xylene, N-methyl-2-pyrrolidone, N,N-dimethylformamide,N,N-dimethylacetamide or a mixture thereof, at a temperature rangingfrom room temperature to reflux and for a time varying from about 1 h toabout 96 h. If a catalyst is required, it is usually a metal, most oftena palladium derivative such as, for instance,tetrakis(triphenylphosphine)paladium(0), palladium(II) chloride orpalladium(II) acetate in the presence of a suitable base such as, forinstance, sodium, potassium or cesium carbonate or cesium fluoride.

According to step h), a compound of formula (IV) can be obtained by atwo-steps reaction sequence from a compound of formula (V) in thepresence of a compound of formula (XIII) in a variety of ways andexperimental conditions known in the art. First step is preferablyconducted in the presence of N-bromosuccinimide with a radical initiatorsuch as benzoyl peroxide or azobisisobutyronitrile in a suitablesolvent, such as carbon tetrachloride, chloroform, dichloromethane ormethyl pivalate, at a temperature ranging from about room temperature toreflux and for a period of time varying from 10 min to about 24 h.Second step can be conducted both under basic or acidic conditions, suchas in the presence of sodium or potassium carbonate,1,8-diazabicyclo[5.4.0]undec-7-ene, triethylamine,diisopropylethylamine, pyridine or acetic acid, hydrochloric acid, in asuitable solvent, such as tetrahydrofuran, dimethoxyethane, 1,4-dioxaneor toluene, at a temperature ranging from room temperature to reflux andfor a period of time varying from 1 h to about 96 h.

According to step c′), the hydrolysis of a compound of formula (IV) togive either a compound of formula (I) or a compound of formula (III),can be carried out in a variety of ways and experimental conditions.Preferably it is carried out in a way analogous to that reported forstep c).

According to step i), when, in a compound of formula (III), X is anitrogen protective group such as tert-butoxycarbonyl, 4-methoxybenzyl,2,4-dimethoxybenzyl and triphenylmethyl protective groups, either acompound of formula (I) or a compound of formula (II) can be obtained byremoving these protective groups under acidic conditions, preferably inthe presence of an inorganic or organic acid such as hydrochloric,trifluoroacetic or methanesulphonic acid, boron tribromide or aluminiumtrichloride, in a suitable solvent, such as dichloromethane,dichloroethane, dioxane or a lower alcohol, such as methanol or ethanol,at a temperature ranging from room temperature to reflux. When, in acompound of formula (III), X is a nitrogen protective group such asbenzyloxycarbonyl and the like, either a compound of formula (I) or acompound of formula (II) can be obtained by removing these protectivegroups under reducing conditions, such as, for instance, in the presenceof hydrogen and a hydrogenation catalyst in a suitable solvent, such asethanol, methanol, ethyl acetate, or a mixture thereof. The catalyst isusually a metal, most often a palladium derivative such as, forinstance, palladium on carbon, palladium hydroxide or paladium black.When, in a compound of formula (III), X is a nitrogen protective groupsuch as methoxycarbonyl, ethoxycarbonyl, 9-fluorenylmethoxycarbonyl andthe like, either a compound of formula (I) or a compound of formula (II)can be obtained by removing these protective groups under basicconditions such as, for instance, sodium, potassium or cesium carbonate,sodium, potassium or barium hydroxide, hydrazine, piperidine, morpholineor the like, in a suitable solvent, such as methanol, ethanol, water,N,N-dimethylformamide, N,N-dimethylacetamide or the like, at atemperature ranging from room temperature to reflux.

According to step l), the reductive alkylation of a compound of formula(II), in the presence of a compound of formula (XIV), to give a compoundof formula (I), can be conducted in a variety of ways, according toconventional methods for carrying out reductive amination. Preferably,this reaction is carried out in a suitable solvent such as, forinstance, methanol, N,N-dimethylformamide, dichloromethane,tetrahydrofuran, benzene, toluene, or a mixture thereof, in the presenceof a suitable reducing agent such as, for instance, sodium borohydride,tetraalkylammonium borohydride, sodium cyano borohydride, sodiumtriacetoxyborohydride, tetramethylammonium triacetoxy borohydride and inthe presence of an acid or basic catalyst, such as, for instance, aceticacid, trifluoroacetic acid, zinc chloride, zinc bromide, tin(IV)chloride, titanium(IV) chloride, boron trifluoride or triethylamine,diisopropylethylamine or pyridine, at a temperature ranging from about0° C. to reflux and for a time varying from about 1 h to about 96 h.

According to step m), a compound of formula (XVI) can be obtained fromfuran-2-carbaldehyde (XV) through reductive amination in the presence ofa compound of formula (XIII). Preferably, this reaction is carried outin a suitable solvent such as, for instance, methanol,N,N-dimethylformamide, dichloromethane, tetrahydrofuran, benzene,toluene, or a mixture thereof, in the presence of a suitable reducingagent such as, for instance, sodium borohydride, tetraalkylammoniumborohydride, sodium cyano borohydride, sodium triacetoxyborohydride ortetramethylammonium triacetoxy borohydride, and in the presence of anacid or basic catalyst, such as, for instance, acetic acid,trifluoroacetic acid, zinc chloride, zinc bromide, tin(IV) chloride,titanium(IV) chloride, boron trifluoride or triethylamine,diisopropylethylamine or pyridine, at a temperature ranging from about0° C. to reflux and for a time varying from about 1 h to about 96 h.

According to step n), the Diels-Alder reaction, performed on a compoundof formula (XVI) to give a compound of formula (XVII), can be conductedin a variety of ways, according to conventional methods for carrying outthese reactions. Preferably, this reaction is carried out in a suitablesolvent such as, for instance, tetrahydrofuran, benzene, toluene oro-xylene, in the presence of maleic anhydride at a temperature rangingfrom about room temperature to reflux and for a time varying from about1 h to about 96 h.

According to step o), the transformation of a compound of formula (XVII)into either a compound of formula (XVIII) or a compound of formula(XIX), can be carried out in a variety of ways, according toconventional methods. Preferably, this reaction is carried out in asuitable solvent such as, for instance, tetrahydrofuran, toluene orwater, in the presence of hydrochloric acid, p-toluenesulfonic acid orphosphoric acid, at a temperature ranging from about room temperature toreflux and for a time varying from about 1 h to about 24 h.

According to step p), a compound of formula (XVIII) can be reactedeither to deliver a compound of formula (I) or a compound of formula(XX) in a variety of ways and experimental conditions, which are widelyknown in the art of condensation reactions. Preferably a compound offormula (XVIII) is reacted with ammonia or ammonia source such asammonium salts, in the presence of an activating agent such ascarbonyldiimidazole, benzotriazol-1-yloxy)tris(dimethylamino)phosphoniumhexafluorophosphate, 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluroniumtetrafluoroborate),(O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate, dicyclohexyl carbodiimide, diisopropyl carbodimide,1-ethyl-3-(3′-dimethylamino) carbodiimide hydrochloric acid salt,optionally in the presence of hydroxybenzotriazole. Preferably, thisreaction is carried out in a suitable solvent such as, for instance,N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran,dichloromethane or 1,4-dioxane, and in the presence of a protonscavenger such as, for example, pyridine, triethylamine ordiisopropylethylamine, at a temperature ranging from room temperature toreflux, for a time ranging from about 30 min to about 96 h.

According to step i′), the deprotection of a compound of formula (XX) togive a compound of formula (XXI), can be carried out in a variety ofways and experimental conditions. Preferably it is carried out in a wayanalogous to that reported for step i).

According to step l′) the reductive alkylation of a compound of formula(XXI), in the presence of a compound of formula (XIV), to give acompound of formula (I), can be carried out in a variety of ways andexperimental conditions. Preferably it is carried out in a way analogousto that reported for step l).

According to step q), the protection of compound of formula (XIX) togive a compound of formula (XVIII), where X is a suitable nitrogenprotective group, may be carried out in a variety of ways andexperimental conditions. Preferably, when the protective group istert-butoxycarbonyl, the reaction may be carried out in the presence ofdi-tert-butyl dicarbonate in a variety of solvents such as methanol,ethanol, acetonitrile, tetrahydrofuran or dichloromethane, in thepresence of a base, such as pyridine. N,N-dimethylaminopyridine,triethylamine, diisopropylethylamine, sodium or potassium carbonate, ata temperature ranging from room temperature to reflux and for a timevarying from about 1 h to about 96 h.

According to the conversion 1 (Cv1), the reductive alkylation of acompound of formula (I) to give another compound of formula (I) may becarried out in a variety of ways and experimental conditions.Preferably, it is carried out in a way analogous to that reported forstep l).

Substituted isoindolinone derivatives can be prepared using standardprocedures in organic synthesis as reported, for instance, in Smith,Michael—March's Advanced Organic Chemistry: reactions mechanisms andstructure—6^(th) Edition, Michael B. Smith and Jerry March, John Wiley &Sons Inc., New York (N.Y.), 2007. It is known to the skilled person thattransformation of a chemical function into another may require that oneor more reactive centers in the compound containing this function haveto be protected in order to avoid undesired side reactions. Protectionof such reactive centers, and subsequent deprotection at the end of thesynthetic transformations, can be accomplished following standardprocedures described, for instance, in: Green, Theodora W. and Wuts,Peter G. M.—Protective Groups in Organic Synthesis, Third Edition, JohnWiley & Sons Inc., New York (N.Y.), 1999.

In cases where a compound of formula (I) contains one or more asymmetriccenters, said compound can be separated into the single isomers byprocedures known to those skilled in the art. Such procedures comprisestandard chromatographic techniques, including chromatography using achiral stationary phase, or crystallization. General methods forseparation of compounds containing one or more asymmetric centers arereported, for instance, in Jacques, Jean; Collet, André: Wien, SamuelH.—Enantiomers, Racemates, and Resolutions, John Wiley & Sons Inc., NewYork (N.Y.), 1981.

A compound of formula (I) can also be transformed into apharmaceutically acceptable salt according to standard procedures thatare known to those skilled in the art. Alternatively, a compound offormula (I) that is obtained as a salt can be transformed into the freebase or the free acid according to standard procedures that are known tothe skilled person.

The starting materials of the process of the present invention, i.e.4-fluoro-2-methyl-phenylamine (XI), 4-fluoro-2-methyl-benzoic acid(XII), furan-2-carbaldehyde (XV) and compounds of formula (XIII) and(XIV) are either commercially available or can be prepared by usingwell-known methods.

Pharmacology

PARP-1 is a DNA damage-induced polymerase that catalyzes the cleavage ofNAD+ into nicotinamide and ADP-ribose and then uses the latter tosynthesize branched nucleic-acid like poly(ADP-ribose) polymers. Invivo, the most abundantly poly (ADP-ribosylated) protein is PARP-1itself, followed by histones. PARP-1 is responsible for 90% of this DNAdamage-induced activity while the remaining 10% is due to PARP-2.

Biochemical Assay

Affinity evaluation of the tested compounds and their selectivity withrespect to the different PARP isoforms of interest was assessed in adisplacement assay.

The identification of compounds capable of binding several PARP proteinsis carried out through a screening method including the steps of

a) providing a reaction mixture containing:

the PARP protein isoform under investigation,

a compound of formula (IP):

wherein R₁₁ is hydrogen or a methyl group, B is (CH₂)_(n)—NH groupwherein n is 2 to 6; m is 0 or 1 and X′″ is a counterion, and

serial dilutions of the test compound:

b) comparing the polarization signal generated in the absence of thetest compound with the one generated in the presence of differentconcentrations of the test compound, and

c) evaluating the ability of the test compound to displace the compoundof formula (IP) as defined above indicated from a decreased fluorescencepolarization level.

Preferably, for the screening method above cited, both the PARP proteinand the 5H-phenanthridin-6-one-derived probe of formula (IP) arepre-mixed, or the PARP protein and the test compound are pre-mixed. In afurther preferred screening method, the PARP proteins are PARP-1, PARP-2and PARP-3. The term “PARP protein” encompasses full-length nativeproteins as well as fragments thereof. More preferably, R₁₁ is hydrogenor methyl, m is 0 or 1; when m is 1, n is 3 or 6, X′″ istrifluoroacetate. The 5H-phenanthridin-6-one-derived probe (IP) wasselected for its capability of binding to the PARP proteins, bothencompassing full-length native proteins and fragments thereof.

The polarization signal can be measured, e.g., by a plate reader such asthe Saphire2 (Tecan). Data analysis was performed, e.g., by using theDynafit software. Displacement data were also fitted, e.g., by usingExcel spreadsheet (Microsoft Inc. Seattle, USA) to a four parameterlogistic model (4PL), or Hill-Slope model. The assay was used to testcompounds of the present invention. The displacement ability of the testcompounds of formula (I) is in correlation with the compounds affinityfor the NAD pocket of the enzyme. Specific probes of formula (IP) usedin the assay are:

-   P1.    9-Dimethylamino-11,11-dimethyl-1-(3-{methyl-[(6-oxo-5,6-dihydro-phenanthridin-2-ylcarbamoyl)-methyl]-carbamoyl}-propyl-2,3,4,11-tetrahydro-naphtho[2,3-g]quinolinium    trifluoroacetate;-   P2.    9-Dimethylamino-11,11-dimethyl-1-[3-(3-{[(6-oxo-5,6-dihydro-phenanthridin-2-ylcarbamoyl)-methyl]-amino}-propylcarbamoyl)-propyl])-2,3,4,11-tetrahydro-naphtho[2,3-g]quinolinium    trifluoroacetate;-   P3.    9-Dimethylamino-11,11-dimethyl-1-[3-(6-{[(6-oxo-5,6-dihydro-phenanthridin-2-ylcarbamoyl)-methyl]-amino}-hexylcarbamoyl)-propyl]-2,3,4,11-tetrahydro-naphtho[2,3-g]quinolinium    trifluoroacetate.

A compound of formula (IP) as defined above can be prepared as describedin WO 2010/133647.

The assay is based on the use of a probe of formula (IP) that binds tothe NAD binding pocket and takes advantage of the significant change inthe polarization signal observed upon binding of the probe to PARP-1, -2and -3. The ability of the probe of formula (IP) to bind full-lengthPARP-1, -2 and -3 has been previously reported (WO 2010/133647). Theassay has been validated as described in WO 2010/133647.

Affinity binding constants (Kd) and DC₅₀s (the compound concentration atwhich the polarization signal is diminished by 50% compared to untreatedcontrols) of the test compounds can be determined as explained in WO2010/133647. The assay, by using either probe P1 or probe P3, was usedto evaluate the biochemical potency of compounds of formula (I), asreported in Table 1.

TABLE 1 PARP-1 PARP-1 PARP-2 PARP-2 PARP-3 PARP-3 Com- (DC₅₀ (Kd (DC₅₀(Kd (DC₅₀ (Kd pound μM) μM) μM) μM) μM) μM)  (2) <0.25† <0.03† 0.34 0.18— —  (3) <0.25 <0.03 7.1 5.8  — —  (4) 0.39 — 1.92 — — —  (5) 0.33 —1.64 — — —  (6) <0.25 0.04 7.44 5.87 — —  (7) <0.25 0.06 0.76 0.42 — — (8) <0.25 0.05 >10 — — —  (9) <0.25 <0.03 4.94 1.44 — — (10) <0.25 0.078.4 6.8  — — (11) <0.25 <0.01*† 2.53 1.4  2.06 — (12) <0.25 <0.03 3.371.7  — — (13) <0.25 <0.03 5.08 — — — (14) <0.25 <0.03 1.25 0.58 — — (15)<0.25 0.04 >10 — 0.9  — (16) <0.25 <0.03 2.88 0.98 — — (17) <0.25 <0.030.63 0.29 — — (19) <0.25 <0.03 2.76 1.39 — — (20) <0.25 <0.03 0.58 0.19— — (21) 0.28 — >10 — — — (22) <0.25 <0.03 2.12 — — — (23) <0.25 <0.032.00 — — — (24) <0.25 <0.03 0.83 044    — — (25) <0.25 — 5.57 — — — (26)3.33 — >10 — — — (27) 1.05 — >10 — — — (28) <0.25 <0.03 1.81 — 5.48 —(29) <0.25 <0.01*† 2.92 — 1.00 — (30) <0.25 — >10 — 0.35 — (31) <0.25— >10 — — — (32) <0.25 0.048 1.88 0.66 — — *Assay performed withcompound P3 as the probe. In all other cases compound P1 was used as theprobe. †Assay sensitivity limits based on a fitting error <50%.

From the above data, it is clear to a person skilled in the art thatcompounds of formula (I) of the present invention are highly potent asPARP-1 inhibitors and extremely selective versus PARP-2 and PARP-3(compare PARP-1, PARP-2 and PARP-3 DC₅₀ and Kd values in Table 1 above).

Cellular Assays

PAR Assay

Cellular activity of PARP-1 inhibitors was assessed by measuring theinhibition of the hydrogen peroxide induced PAR formation in HeLa cells(ECACC). Cellular PAR levels were measured by immunocytochemistry, andquantified using an ArrayScan vTi instrument (Cellomics ThermoScientific).

Studies were performed as follows: 6000 cells/well were seeded in 96well plates (Perkin Elmer) in MEM/10% FCS and incubated for 24 h at 37°C., 5% carbon dioxide. Test compounds were then added at the requiredconcentration for 30 min. DNA damage was then induced adding hydrogenperoxide at the concentration of 0.1 mM for 15 min. Concentration curveswere prepared in MEM/10% FCS from compound stocks in DMSO, and finalDMSO concentration was 0.002% (v/v). Duplicate wells for eachconcentration point were prepared with a typical highest compoundconcentration of 20 μM and serial dilution 1:3. Plates were dried andfixed adding cold methanol-acetone (70:30) solution for 15 min at roomtemperature, fixing solution was aspired and wells were air dried for 5min and then dehydrated in PBS. Non-specific binding sites were blockedby incubating wells for 30 min in PBS containing 5% (w/v) FBS 0.05%tween 20. Wells were then incubated for 1 h at room temperature in PBScontaining anti PAR mouse monodonal antibody (Anti-PAR, Mouse mAb 10H,Tulip Cat No 1020) diluted 1:200 in blocking solution. After 3 washes inPBS, wells incubated in PBS (w/v) 5% FBS 0.05% Tween20 containing 2μg/mL Cy2-conjugated Goat anti mouse secondary antibody (AmershamPharmacia Biotech cat. No PA 42002) (Absorption maximum 489 nmfluorescence maximum 506 nm) and 1 μg/mL DAPI (Absorption maximum 359 nmfluorescence maximum 461 nm) (4′,6-diamidino-2-phenyindole dilactate)(Sigma cat. No D9564), a high-sensitivity dye for nucleic acid staining.After washing further 3 times in PBS, cellular PAR immunoreactivity wasassessed using the ArrayScan vTi instrument, with a Zeiss 10× 0.5 NAobjective, and applying the Cytotoxicity. V3 algorithm (Cellomics/ThermoFisher) with a XF100 filter. At least 10 fields, corresponding to atleast 900 cells, were read for each well. IC₅₀ Values represent thecompound concentration at which cellular PAR signal is diminished by 50%compared with untreated controls. The following formula is used:IC₅₀=Bottom+(Top−Bottom)/(1+10{circumflex over ( )}((Log EC₅₀−X)));

X is the logarithm of concentration, IC₅₀ is the response; IC₅₀ startsat bottom and goes to top with a sigmoid shape. Given the above assays,compounds of formula (I) of the present invention inhibited PARformation with IC₅₀ values lower than 5 μM, as depicted in Table 2.

TABLE 2 Compound PAR assay (IC₅₀ μM)  (3) 2.25  (6) 2.15  (9) 1.40 (11)0.02 (12) 3.9 (13) 0.98 (14) 0.011 (15) 0.1 (16) 0.02 (17) 1.51 (19)0.33 (20) 0.83 (21) 0.60 (22) 0.40 (23) 0.40 (24) 0.11 (25) 0.20 (28)0.56 (29) 0.5 (31) 0.2 (32) 0.17

Colony Forming Assay

MDA-MB-436 breast cancer BRCA-1 mutated cells were grown at the densityof 600 cells/cm² in RPMI medium supplemented with 10% Fetal BovineSerum. 24 h later different doses of compounds were added starting from10 μM concentration in duplicates. Ten days later, cells were fixed andstained with crystal violet. Colonies were counted using InfraredScanner (Odyssey Li-Cor). Anti proliferative IC₅₀ was calculated usingPrism.

Pharmacokinetics

The pharmacokinetic profile and the oral bioavailability of thecompounds have been investigated in the mouse (Balb,Nu/Nu, Harlan,Italy) in ad hoc pharmacokinetic studies. The compounds were formulatedin 10% tween 80/dextrose for intravenous bolus administration while oraladministrations were performed using the compounds formulated in 0.5%methylcellulose. A single administration at the dose of 10 mg/kg wasgiven and three male animals for each route were used. All blood sampleswere taken from retro-orbital vein at 5 min, 30 min, 1 h, 3 h, 6 h, 24 hafter intravenous administration and 15 min, 30 min, 1 h, 3 h, 6 h, 24 hafter oral administration. Plasma samples were prepared by plasmaproteins precipitation adding 200 μL of acetonitrile to 20 μL of plasmain a 96 well plate. After capping and vortex mixing, the plate wascentrifuged for 15 min at 4000 rpm. The supernatant was considered asfinal extract and injected onto the LC-MS-MS system (UPLC system: WatersAcquity using BEH C18 50*2.1 mm 1.7 μm analytical column; MS instrument:Waters TQD equipped with Electro-Spray source operating in positive ionmode). Lower limit of quantification is 5.0 ng/mL, upper limit ofquantification is 5000 ng/mL. Non-compartmental method (lineartrapezoidal rule and linear regression analysis of naturallog-transformed plasma concentrations vs. time data) was used Absolutebioavailability (F) was calculated from the ratio of average oral to IV(intravenous) dose-normalized plasma AUC (area under curve) values.

The abbreviations used herein have the following meaning:

AUC (area under the plasma concentration vs. time curve up to the lastdetectable concentration)

Cl (plasma clearance)

Cmax (maximum plasma concentration)

T½ (terminal half life)

Vdss (volume of distribution at steady state)

Some representative compounds of formula (I) were evaluated for theirpharmacokinetic parameters as reported in Table 3 as mean value.

TABLE 3 Cl(IV Vdss (IV AUC Cmax T½ F on Com- bolus) bolus) (oral) (oral)(oral) AUC pound mL/min/kg L/Kg μM · h μM h %  (3) 63.1 1.54 2.51 3.060.68 30 (11) 41.3 4.47 20.4 3.87 2.72 100 (14) 81.8 2.68 3.22 2.29 0.8957 (15) 16.9 0.79 19.2 8.73 1.01 68 (16) 79.3 2.51 2.13 2.97 0.63 37

From the above, it is clear to the person skilled in the art thatcompounds of formula (I) possess good to excellent pharmacokineticsprofiles and oral bioavailability.

In Vivo Efficacy Studies

Balb, athymic Nu/Nu male mice, from Harlan (Italy), were maintained inagreement with the European Communities Council Directive no. 86/609/EECconcerning the protection of animals used for experimental or otherscientific purposes, in cages with paper filter cover, food and beddingsterilized and acidified water. Fragments of Capan-1 human pancreaticcancer tumors were implanted subcutaneously. Mice bearing a palpabletumor (100-200 mm³) were selected and randomized into control andtreated groups. Each group included seven animals. The treatment startedone day after randomization. Compound of formula (I) was administered byoral route as a methocel suspension at the indicated doses and times.Tumor dimension was measured regularly by calipers during theexperiments and tumor mass was calculated as described in Simeoni M. etal., Cancer Res 64, 1094-1101 (2004). The tumor growth inhibition (TGI,%) was calculated according to the equation: % TGI=100−(mean tumorweight of treated group/mean tumor weight of control group)*100.

Some representative compounds of formula (I) were evaluated for theiranti-tumor activity as single agent on Capan-1 BRCA-2 mutated mousemodel and results are reported in table 4. Toxicity was evaluated on thebasis of body weight reduction (no body weight reduction observed out of7 mice treated).

TABLE 4 Compounds Dose Schedule Max TGI (%) Toxicity (11) 75 mg/kg 1-8daily 42% 0/7 (15) 75 mg/kg 1-10 daily 54% 0/7

Representative compounds of formula (I) were evaluated for theiranti-tumor activity on Capan-1 BRCA-2 mutated mouse model in combinationwith temozolomide. Compounds of formula (I) and temozolomide were bothadministered by oral route. Tumor growth was assessed by caliper. Thetwo diameters were recorded and the tumor weight was calculatedaccording to the following formula: length (mm)×width²/2. The effect ofthe antitumor treatment was evaluated as the delay in the onset of anexponential growth of the tumor (see for references Anticancer drugs7:437-60, 1996). This delay (T-C value) was defined as the difference oftime (in days) required for the treatment group (T) and the controlgroup (C) tumors to reach a predetermined size (1 g). Toxicity wasevaluated on the basis of body weight reduction and animal survivalrate. The T-C observed when Compounds of formula (I) were combined withtemozolomide was superior to the one expected by the simple addition ofT-C obtained by the single treatments, thus indicating strong synergism.

Therefore, the present invention provides compounds of formula (I)useful in therapy.

Compounds of formula (I) of the present invention, suitable foradministration to a mammal, e.g., to humans, can be administered by theusual routes and the dosage level depends upon the age, weight,conditions of the patient and administration route.

For example, a suitable dosage adopted for oral administration of acompound of formula (I) may range from about 1 to about 1000 mg perdose, from 1 to 5 times daily. The compounds of the invention can beadministered in a variety of dosage forms, e.g., orally, in the form oftablets, capsules, sugar or film coated tablets, liquid solutions orsuspensions; rectally in the form of suppositories; parenterally, e.g.,intramuscularly, or through intravenous and/or intrathecal and/orintraspinal injection or infusion.

As stated above, the present invention also includes pharmaceuticalcompositions comprising a compound of formula (I) or a pharmaceuticallyacceptable salt thereof in association with a pharmaceuticallyacceptable excipient, which may be a carrier or a diluent.

The pharmaceutical compositions containing the compounds of theinvention are usually prepared following conventional methods and areadministered in a suitable pharmaceutical form. For example, the solidoral forms may contain, together with the active compound, diluents,e.g., lactose, dextrose, saccharose, sucrose, cellulose, corn starch orpotato starch; lubricants, e.g., silica, talc, stearic acid, magnesiumor calcium stearate, and/or polyethylene glycols; binding agents, e.g.,starches, arabic gum, gelatine methylcellulose, carboxymethylcelluloseor polyvinyl pyrrolidone: disintegrating agents, e.g., starch, alginicacid, alginates or sodium starch glycolate; effervescing mixtures;dyestuffs; sweeteners; wetting agents such as lecithin, polysorbates,laurylsulphates; and, in general, non-toxic and pharmacologicallyinactive substances used in pharmaceutical formulations. Thesepharmaceutical preparations may be manufactured in known manner, forexample, by means of mixing, granulating, tabletting, sugar-coating, orfilm-coating processes.

The liquid dispersions for oral administration may be, e.g., syrups,emulsions and suspensions. As an example, the syrups may contain, ascarrier, saccharose or saccharose with glycerine and/or mannitol andsorbitol.

The suspensions and the emulsions may contain, as examples of carriers,natural gum, agar, sodium alginate, pectin, methylcellulose,carboxymethylcellulose, or polyvinyl alcohol. The suspension orsolutions for intramuscular injections may contain, together with theactive compound, a pharmaceutically acceptable carrier, e.g., sterilewater, olive oil, ethyl oleate, glycols, such as propylene glycol, and,if desired, a suitable amount of lidocaine hydrochloride.

The solutions for intravenous injections or infusions may contain, as acarrier, sterile water or preferably they may be in the form of sterile,aqueous, isotonic, saline solutions or they may contain propylene glycolas a carrier.

The suppositories may contain, together with the active compound, apharmaceutically acceptable carrier, e.g., cocoa butter, polyethyleneglycol, a polyoxyethylene sorbitan fatty acid ester surfactant orlecithin.

EXPERIMENTAL SECTION

For a reference to any specific compound of formula (I) of theinvention, optionally in the form of a pharmaceutically acceptable salt,see the experimental section and claims. Referring to the examples thatfollow, compounds of the present invention were synthesized using themethods described herein, or other methods, which are well known in theart.

The short forms and abbreviations used herein have the followingmeaning:

-   amu (atomic mass unit)-   calcd. (calculated)-   μM (micromolar)-   μL (microliter)-   μm (micrometer)-   mol (moles)-   mM (millimolar)-   mmol (millimoles)-   nm (nanometers)-   g (grams)-   mg (milligrams)-   ng (nanograms)-   h (hour/s)-   min (minute/s)-   DC₅₀ (the half maximal Displacement Concentration)-   IC₅₀ (the half maximal Inhibitory Concentration)-   PAR (poly (ADP-ribose))-   MEM (Minimal Essential Medium)-   FCS (Fetal Calf Serum)-   FBS (Fetal Bovine Serum)-   PBS (Phosphate Buffered Saline)-   LC-MS (Liquid Chromatography-Mass Spectrometry)-   HPLC (High Performance Liquid Chromatography)-   TLC (Thin Layer Chromatography)-   MHz (megahertz)-   Hz (Hertz)-   DMSO-ds (deuterated dimethylsulfoxide)-   CDCl₃ (deuterated chloroform)-   ESI (electrospray ionization)

With the aim at better illustrating the present invention, withoutposing any limitation to it, the following examples are now given.

As used herein the symbols and conventions used in the processes,schemes and examples are consistent with those used in the contemporaryscientific literature, for example, the Journal of the American ChemicalSociety or the Journal of Biological Chemistry.

Unless otherwise noted, all materials were obtained from commercialsuppliers, of the best grade and used without further purification.Anhydrous solvent such as N,N-dimethylformamide, tetrahydrofuran,dichloromethane and toluene were obtained from the Aldrich ChemicalCompany. All reactions involving air- or moisture-sensitive compoundswere performed under nitrogen or argon atmosphere.

General Purification and Analytical Methods

Flash Chromatography was performed on silica gel (Merck grade 9395, 60Å). HPLC was performed on Waters X Terra RP 18 (4.6×50 mm, 3.5 μm)column using a Waters 2790 HPLC system equipped with a 996 Waters PDAdetector and Micromass mod. ZQ single quadrupole mass spectrometer,equipped with an electrospray (ESI) ion source. Mobile phase A wasammonium acetate 5 mM buffer (pH 5.5 with acetic acid-acetonitrile95:5), and mobile phase B was water-acetonitrile (5:95). Gradient from10 to 90% B in 8 min, hold 90% B 2 min. UV detection at 220 nm and 254nm. Flow rate 1 mL/min. Injection volume 10 μL. Full scan, mass rangefrom 100 to 800 amu. Capillary voltage was 2.5 KV; source temperaturewas 120° C.; cone was 10 V. Retention times (HPLC r.t.) are given in minat 220 nm or at 254 nm. Mass are given as m/z ratio.

When necessary, compounds were purified by preparative HPLC on a WatersSymmetry C18 (19×50 mm, 5 μm) column or on a Waters X Terra RP 18(30×150 mm, 5 μm) column using a Waters preparative HPLC 600 equippedwith a 996 Waters PDA detector and a Micromass mod. ZMD singlequadrupole mass spectrometer, electron spray ionization, positive mode.Mobile phase A was water-0.01% trifluoroacetic acid, and mobile phase Bwas acetonitrile. Gradient from 10 to 90% B in 8 min, hold 90% B 2 min.Flow rate 20 mL/min. In alternative, mobile phase A was water-0.1%ammonium hydroxide, and mobile phase B was acetonitrile. Gradient from10 to 100% B in 8 min, hold 100% B 2 min. Flow rate 20 mL/min.

¹H-NMR spectra were performed in DMSO-d₆ or CDCl₃ on a Varian Inova 400operating at 400.5 MHz and on a Varian Mercury 300 operating at 300.0MHz. ¹³C NMR spectra were performed in DMSO-d₆ at 75.0 MHz.

Residual solvent signal was used as reference (8=2.50 or 7.27 ppm).Chemical shifts (6) are reported in parts per million (ppm) and couplingconstants (J) in Hz. The following abbreviations are used formultiplicities: s=singlet; br. s.=broad signal; d=doublet; t=triplet;m=multiplet; dd=doublet of doublets.

ESI(+) high-resolution mass spectra (HRMS) were obtained on a Q-TofUltima (Waters, Manchester, UK) directly connected with a 1100micro-HPLC system (Agilent, Palo Alto, US) as previously described(Colombo, M., Sirtori, F. R., and Rizzo, V. (2004) A fully automatedmethod for accurate mass determination using high-performance liquidchromatography with a quadrupole/orthogonal acceleration time-of-flightmass spectrometer. Rapid Commun. Mass Spectrom. 18, 511-517).

Example 1

Step a

2-Bromo-4-fluoro-6-methyl-phenylamine (X) [Hal=Br]

A solution of N-bromosuccinimide (18.7 g, 0.105 mol) in 70 mL ofN,N-dimethylformamide was added dropwise to a solution of4-fluoro-2-methyl-phenylamine (XI) (12.5 g, 0.1 mol) in 70 mL of thesame solvent at 20° C. The reaction mixture was stirred overnight. Thedark solution was poured into a mixture of water (1000 mL), brine (50mL) and ethyl acetate (300 mL). The mixture was transferred into aseparatory funnel, shaken and separated. The aqueous phase was extractedwith ethyl acetate (4×150 mL). The combined organic layers were washedwith water (5×100 mL), brine (2×100 mL), dried over Na₂SO₄, filtered andconcentrated. The product was purified by flash chromatography (eluentethyl acetate:n-hexane=1:8). The pure fractions were combined andevaporated to give 14.9 g of product. The impure fractions werecombined, concentrated, re-dissolved in diethyl ether (30 mL) andextracted with 5% hydrochloric acid (5×10 mL). The acyclic phase wasbasified with aqueous potassium hydroxide and extracted with diethylether to provide further 0.8 g of the title compound. Total yield was15.7 g (77%).

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 2.16 (s, 3H), 4.83 (br. s, 2H), 6.91(dd, J_(H-F)=9.3 Hz, J_(H-H)=2.9 Hz, 1H), 7.16 (dd, J_(H-F)=8.3 Hz,J_(H-H)=2.9 Hz, 1H).

Step b

2-Bromo-4-fluoro-6-methyl-benzonitrile (IX) [Hal=Br]

A solution of potassium cyanide (16.25 g, 0.25 mol) in 20 mL of waterwas added to a suspension of freshly prepared copper(I) chloride (9.5 g,0.096 mol) in 40 mL of water. Toluene (30 mL) was then added and themixture was chilled to 0° C. 2-Bromo-4-fluoro-6-methyl-phenylamine (X)(15.7 g, 0.077 mol) was added to a mixture of 16.5 ml of 36% aqueoushydrochloric acid and 40 mL of water. The resultant suspension washeated until a solution was formed. The solution was chilled to 2° C.and the amine hydrochloride precipitated. A solution of sodium nitrite(5.34 g, 0.078 mol) in 15 mL of water was slowly added, keeping thereaction mixture temperature below 5° C. Powdered sodium carbonatedecahydrate was added in small portions to adjust the pH of the reactionmixture to about 7. The resultant solution of the diazonium salt wasthen slowly added to the previously prepared cyanocuprate reagent, againkeeping the reaction temperature below 5° C. A bright red-orangeprecipitate formed. The reaction mixture was allowed to warm to 20° C.and kept at this temperature overnight. Then it was slowly heated to 70°C. for 1 h. The precipitate dissolved almost completely. The reactionmixture was allowed to cool to 20° C. and filtered. The organic phasewas separated, and the aqueous phase was extracted with toluene (3×70mL). The combined organic layers were washed with water (2×100 mL),brine (2×100 mL), dried over Na₂SO₄, filtered and concentrated. Thecrude nitrile (IX) (13.9 g, 84%) was used without further purification.

¹H NMR (400.5 MHz, DMSO-d₃) δ ppm 2.52 (s, 3H), 7.44 (dd, J_(H-F)=9.4Hz, J_(H-H)+=2.1 Hz, 1H), 7.73 (dd, J_(H-F)=8.2 Hz, J_(H-H)=2.1 Hz, 1H).

¹³C NMR (75.0 MHz, DMSO-d₆) δ 115.8, 112.7 (d, J_(C-F)=3 Hz), 117.0 (d,J_(C-F)=23 Hz), 118.4 (d, J_(C-F)=27 Hz), 126.1 (d, J_(C-F)=11 Hz),147.8 (d, J_(C-F)=11 Hz), 163.5 (d, J_(C-F)=257 Hz).

Step c

2-Bromo-4-fluoro-6-methyl-benzamide (VIII) [Hal=Br]

2-Bromo-4-fluoro-6-methyl-benzonitrile (IX) (0.428 g, 2 mmol) was heatedin 70% aqueous sulfuric acid (2 mL) overnight at 150° C. The reactionmixture was poured into ice and extracted with ethyl acetate (4×2 mL).The organic phase was washed with water (4×2 mL), brine (2×2 mL), driedover Na₂SO₄, filtered and concentrated to give 300 mg of crude2-bromo-4-fluoro-6-methyl-benzamide (VIII). Pure sample was obtained byrecrystallization from benzene.

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 3.31 (s, 3H), 7.17 (dd, J_(H-F)=9.8Hz, J_(H-H)=2.2 Hz, 1H), 7.41 (dd, J_(H-F)=8.6 Hz, J_(H-H)=2.2 Hz, 1H),7.89 (br. s, 1H), 7.65 (br. s, 1H).

Step d

2-Bromo-4-fluoro-1-methyl-benzoic Acid (VII) [Hal=Br]

2-Bromo-4-fluoro-6-methyl-benzamide (VIII) (0.9 g, 3.9 mmol) wasdissolved in 75% aqueous sulfuric acid (4 mL) at 80° C. Sodium nitrite(0.5 g, 7.2 mmol) was carefully added in small portions during 1 h. Thereaction mixture was chilled to 20° C. and cold water (15 ml) was addedto the reaction mixture. The product was extracted with ethyl acetate(6×2 mL). The organic phase was washed with water (4×2 mL), brine (2×2mL), dried over Na₂SO₄, filtered and concentrated to give 0.879 g (97%)of pure acid (VII).

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 2.31 (s, 1H), 7.22 (dd, J_(C-F)=9.6Hz, J_(H-H)=2.2 Hz, 1H), 7.47 (dd, J_(H-F)=8.5 Hz, J_(H-H)=2.4 Hz, 1H),13.7 (br. s, 1H).

¹³C NMR (75.0 MHz, DMSO-d₆+CCl₄) δ ppm 19.5, 116.0 (d, J_(C-F)=22 Hz),116.8 (d, J_(C-F)=24 Hz), 118.3 (d, J_(C-F)=10 Hz), 134.0 (d, J_(C-F)=3Hz), 138.4 (d, J_(C-F)=8 Hz), 163.0 (d, J_(C-F)=250 Hz), 168.0.

Step f

2-Bromo-4-fluoro-6-methyl-benzoic Acid Methyl Ester (VI) [Hal=Br;T=methyl]

A mixture of 2-bromo-4-fluoro-6-methyl-benzoic acid (VII) (1.94 g, 8.33mmol), anhydrous potassium carbonate (1.72 g, 12.5 mmol), methyl iodide(2.36 g, 17 mmol) in N,N-dimethylformamide (15 mL) was vigorouslystirred for 23 h at 20° C. The suspension was poured into 70 mL ofwater. A dense oil separated out. The product was extracted with ethylacetate (4×25 mL). The organic phase was washed with water (5×20 mL),brine (2×20 mL), dried over Na₂SO₄, filtered and concentrated to give2.07 g (quantitative yield) of 2-bromo-4-fluoro-6-methyl-benzoic acidmethyl ester (VI).

¹H NMR (400.5 MHz, CDCl₃) δ ppm 2.35 (s, 3H), 3.96 (s, 3H), 6.91 (dd,J_(H-F)=9.0 Hz, J_(H-H)=2.2 Hz, 1H), 7.18 (dd, J_(H-F)=8.1 Hz,J_(H-H)=2.4 Hz, 1H).

Step g

2-Cyano-4-fluoro-6-methyl-benzoic Acid Methyl Ester (V) [T=methyl]

A mixture of 2-bromo-4-fluoro-6-methyl-benzoic acid methyl ester (VI)(275 mg, 1.12 mmol), potassium hexacyanoferrate (II) (206 mg, 0.56mmol), anhydrous sodium carbonate (237 mg, 2.24 mmol) and palladium(II)acetate (5 mg, 0.0224 mmol) in 3 mL of N-methylpyrrolidone was heated at120° C. in a sealed tube under argon atmosphere overnight. The reactionmixture was diluted with dichloromethane and filtered through a pad ofCelite. The organic phase was washed with water (13×6 mL), brine (2×6mL), dried over Na₂SO₄, filtered and concentrated. Column chromatography(n-hexane/ethyl acetate:7/3) afforded 2-cyano-4-fluoro-6-methyl-benzoicacid methyl ester (76 mg, 35%).

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 2.42 (s, 3H), 3.93 (s, 3H), 7.65 (dd,J_(HF)+=9.6, J_(HH)=2.6 Hz, 1H), 7.85 (dd, J_(HF)=8.3, 2.6 Hz, 1H).

Step h

6-Fluoro-2-(3-morpholin-4-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carbonitrile(IV) [n=3; R1=morpholin-4-yl: X=null, as m=0 and R2=null]

To a solution of 2-cyano-4-fluoro-6-methyl-benzoic acid methyl ester (V)(208 mg, 1.07 mmol) in methyl pivalate (2 mL), N-bromosuccinimide (310mg, 1.74 mmol) and benzoylperoxide (20 mg, 0.097 mmol) were added. Thereaction mixture was stirred at 85° C. under nitrogen atmosphere for 3h. Crude was filtered on Gooch and washed with toluene. Volatiles wereevaporated and the residue was dissolved in acetonitrile (3 mL).Triethylamine (0.41 mL, 2.9 mmol) and 3-morpholin-4-yl-propylamine(XIII) (140 mg, 0.97 mmol) were added and the reaction mixture wasstirred at 90° C. for 3 h. Crude was diluted with dichloromethane andwashed with 15% ammonium hydroxide. The organic phase was dried overNa₂SO₄, filtered and evaporated. Column chromatography (gradient fromchloroform/methanol: 96/4 to chloroform/methanol:94/6) afforded6-fluoro-2-(3-morpholin-4-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carbonitrile(IV) (130 mg, 40% yield).

¹H NMR (400.5 MHz, CDCl₃) δ ppm 1.87 (quintet, J=7.1 Hz, 2H), 2.34-2.49(m, 6H), 3.62-3.74 (m, 6H), 4.45 (s, 2H), 7.42 (dd, J_(H-F)=7.3 Hz,J_(H-H)=2.0 Hz, 1H), 7.47 (dd, J_(H-F)=8.3 Hz, J_(H-H)=2.0 Hz, 1H).

Step c′

6-Fluoro-2-(3-morpholin-4-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 23 [R═F; n=3; R1=morpholin-4-yl; m=0; R2=null]

A solution of6-fluoro-2-(3-morpholin-4-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carbonitrile(IV) (100 mg, 0.33 mmol) in 1.5 mL of 36% hydrochloric acid was heatedat 50° C. for 10 h. All volatile materials were evaporated and theresidue was dissolved in 2 mL of cold water. The solution wasneutralized with solid potassium carbonate. The solid precipitated wasdissolved in dichloromethane and the organic phase was washed withsaturated aqueous sodium carbonate (2×1 mL), brine (2×1 mL), dried overNa₂SO₄, filtered and concentrated to give 73 mg (73%) of6-fluoro-2-(3-morpholin-4-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicacid amide (I).

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.79 (quintet, J=7.1 Hz, 2H),2.28-2.35 (m, 6H), 3.47-3.52 (m, 4H), 3.59 (t, J=7.1 Hz, 2H), 4.58 (s,2H), 7.68 (dd, J_(HF)=7.8, J_(HH)=2.6 Hz, 1H), 7.83 (br. s., 1H), 7.89(dd, J_(HF)=10.9, J_(HH)=2.6 Hz, 1H), 10.81 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₈H₂₁FN₃O₃ [M+H]⁺ 322.1562; found 322.1565.

Example 2

Step e

4-Fluoro-2-iodo-6-methyl-benzoic Acid (VII) [Hal=I]

A mixture of 4-fluoro-2-methyl-benzoic acid (XII) (20.00 g, 0.130 mol),iodobenzene diacetate (50.15 g, 0.156 mol), iodine (39.52 g, 0.156 mol)and palladium(II) acetate (1.46 g, 0.006 mol) in N,N-dimethylformamide(360 mL) was degassed by cycling vacuum and nitrogen three times andthen was heated for 18 h at 100° C. internal temperature, under argon.The resultant dark mixture was cooled to room temperature, diluted withmethyl-tert-butylether (200 mL) and treated with a solution of sodiummetabisulfite (250 g) in water (500 mL) under efficient stirring. Then,this yellow colored mixture was acidified by slowly adding conc.hydrochloric add (130 mL). The aqueous layer was separated and extractedtwice with methyl-tert-butylether (mL100×2). The combined organicextracts were treated with a solution of sodium hydroxide pellets (80 g)in water (300 mL) under stirring. The organic layer containing onlyiodobenzene was discharged, while the aqueous layer was added withsodium chloride, cooled to ice temperature and brought to very low pHwith conc. hydrochloric acid (130 mL). From this aqueous medium theproduct was extracted with methyl-tert-butylether (100 mL×3) and thecombined extracts were dried over Na₂SO₄ and finally concentrated underreduced pressure affording 30.5 g (84%) of4-fluoro-2-iodo-6-methyl-benzoic acid as brown solid. This raw materialwas used in the next step without purification.

¹H NMR (300.0 MHz, CDCl₃) δ ppm 2.46 (s, 3H), 6.96 (dd, J_(HF)=9.1,J_(HH)=2.6 Hz, 1H), 7.45 (dd, J_(HF)=7.9. 2.3 Hz, 1H).

Step f

4-Fluoro-2-iodo-6-methyl-benzoic Acid Methyl Ester (VI) [Hal=I;T=methyl]

To a solution of 4-fluoro-2-iodo-6-methyl-benzoic acid (VII) (30.05 g,0.109 mol) in N,N-dimethylformamide (300 mL) was added anhydrouspotassium carbonate (22.0 g, 0.16 mol) under efficient magneticstirring. After 15 min methyl p-toluensulfonate (30.7 g, 0.16 mol) wasadded. The brown suspension was stirred at room temperature for 2 h.Potassium acetate (12.4 g, 0.13 mol) was then added to destroy theunreacted methyl p-toluensulfonate and the mixture was stirredovernight. The thick reaction mixture was diluted withmethyl-tert-butylether (100 mL) and washed with water (600 mL); theaqueous layer was separated and extracted twice withmethyl-tert-butylether (70 mL×2). The combined organic extracts werewashed with brine (50 mL), dried over Na₂SO₄ and concentrated underreduced pressure to a solid residue. This material was purified bychromatography (eluant n-hexane/ethyl acetate 9:1), affording 26.2 g(81%) of product as colorless oil.

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 2.27 (s, 3H), 3.86 (s, 3H), 7.25 (dd,J_(HF)=9.6, J_(HH)=2.4 Hz, 1H), 7.63 (dd, J_(HF)=8.2, J_(HH)=2.4 Hz,1H).

Step g

2-Cyano-4-fluoro-6-methyl-benzoic Acid Methyl Ester (V) [T=methyl]

A solution of 4-fluoro-2-iodo-6-methyl-benzoic acid methyl ester (VI)(26.02 g, 88.48 mmol) in 260 mL of N,N-dimethylformamide was treatedwith copper(I) cyanide (12.18 g; 0.136 mol) and stirred at 110° C. for 5h. The dark colored mixture was allowed to cool to about 60° C., treatedwith 105 g of Celite® 560 coarse (Fluka) under efficient stirring anddiluted with ethyl acetate (250 mL). After cooling to room temperature,the mixture was slowly poured in 0.25N aqueous sodium hydroxide (500 mL)and then filtered. The reaction flask and the panel were washed withethyl acetate (100 mL). The aqueous layer was separated and extractedtwice with ethyl acetate (250 mL+100 mL). The combined organic extractswere washed with brine (200 mL), dried over Na₂SO₄ and concentratedunder reduced pressure to give 22.00 g of raw product as yellow solid.This material was crystallized from n-hexane (40 mL): after cooling toroom temperature the solid was collected by filtration and the motherliquors were concentrated under reduced pressure. The solid residue soobtained was crystallized from n-hexane (20 mL) yielding, afterfiltration of the solids, a second crop of product. The combined crops(14.15 g) were finally purified by chromatography eluting in gradientfrom n-hexane/methyl-tert-butylether 9:1 to n-hexane/ethyl acetate 9:1.After evaporation of the fractions 12.0 g (70%) of2-cyano-4-fluoro-6-methyl-benzoic acid methyl eater (V) were obtained.

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 2.42 (s, 3H), 3.93 (s, 3H), 7.65 (dd,J_(HH)=9.6, J_(HH)=2.6 Hz, 1H), 7.85 (dd, J_(HF)=8.3, 2.6 Hz, 1H).

Step h

2-(1-Cyclohexyl-piperidin-4-yl)-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carbonitrile(IV) [R═F; n=m=0; R1=piperidin-4-yl; R2=1-cyclohexyl]

To a solution of 2-cyano-4-fluoro-6-methyl-benzoic acid methyl ester (V)(208 mg, 1.07 mmol) in methyl pivalate (2 mL), N-bromosuccinimide (310mg, 1.74 mmol) and benzoylperoxide (20 mg, 0.097 mmol) were added. Thereaction mixture was stirred at 85° C. under nitrogen atmosphere for 3h. Crude was filtered and washed with toluene. Volatiles were evaporatedand the residue was dissolved in acetonitrile (3 mL). Potassiumcarbonate (670 mg, 4.85 mmol) and 1-cyclohexyl-piperidin-4-ylaminedihydrochloride monohydrate (XIII) (265 mg, 0.97 mmol) were added andthe reaction mixture was stirred at 90° C. for 3 h. Crude was dilutedwith dichloromethane and washed with 15% ammonium hydroxide. The organicphase was dried over Na₂SO₄, filtered and evaporated. Columnchromatography (dichloromethane/methanol/ammonia solution, 7N inmethanol:972/1) afforded2-(1-cyclohexyl-piperidin-4-yl)-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carbonitrile(IV) (100 mg, 30%).

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.02-1.13 (m, 1H), 1.16-127 (m, 4H),1.55-1.62 (m, 1H), 1.68-1.80 (br. s., 7H), 2.23-2.39 (m, 3H), 2.87-2.97(m, 2H), 3.95 (br. s., 1H), 4.52 (s, 2H), 7.86 (dd, J_(HF)=8.3,J_(HH)=2.2 Hz, 1H), 7.98 (dd, J_(HF)=9.3, J_(HH)=2.2 Hz, 1H).

HRMS (ESI+): calcd. for CH₂₀H₂₅FN₃O [M+H]⁺ 342.1976; found 342.1988.

Step c′

2-(1-Cyclohexyl-piperidin-4-yl)-6-fluoro-3-oz-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 29 [R═F; n=m=0; R1=piperidin-4-yl; R2=1-cyclohexyl]

To a stirred solution of2-(1-cyclohexyl-piperidin-4-yl)-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carbonitrile(IV) (100 mg, 0.3 mmol) in acetic acid (5 mL), concentrated sulfuricacid (2.7 mL) was added dropwise during 30 min. The reaction was thenwarmed at 80° C. for 9 h, cooled at room temperature and poured intocold water (10 mL). The aqueous phase was then made basic by addingconcentrated aqueous ammonia and extracted with dichloromethane (3×10mL). The combined organic phases were washed with 2N aqueous sodiumhydroxide (2×12 mL) and brine, dried over Na₂SO₄ and evaporated todryness in vacuo. The title compound was obtained as a white solid (43mg, 40%) after purification through column chromatography((dichloromethane/methanol/ammonia solution, 7N in methanol:97/2/1).

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.00-1.14 (m, 1H), 1.14-1.28 (m, 4H),1.53-1.61 (m, 1H), 1.67-1.80 (m, 6H), 2.25-2.36 (m, 3H), 2.88-2.95 (m,2H), 3.94-4.03 (m, 1H), 4.55 (s, 2H), 7.66 (dd, J_(HF)=7.7, J_(HH)=2.6Hz, 1H), 7.85 (br. s., 1H), 7.89 (dd, J_(HF)=10.9, J_(HH)=2.6 Hz, 1H),10.78 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₀H₂₇FN₃₂ [M+H]⁺ 3602082: found 360.2098.

Example 3

Step m

4-[(Furan-2-ylmethyl)-amino]-piperidine-1-carboxylic Acid Tert-ButylEster (XVI) [n=0; R1=piperidin-4-yl; X=tert-butoxycarbonyl]

To an equimolar solution of furan-2-carbaldehyde (XV) (250 mg, 2.6 mmol)and 4-amino-piperidine-1-carboxylic acid tert-butyl ester (XIII) (473mg, 2.6 mmol) in dichloromethane (14 mL) 1M titanium(IV) chloride indichloromethane (1.3 mL, 1.3 mmol) and triethylamine (0.32 ml, 2.6 mmol)were added. The reaction mixture was stirred under nitrogen atmospherefor 2 days. Then sodium cyanoborohydride (493 mg, 7.8 mmol) in methanol(7 mL) was added dropwise with stirring and the solution was allowed tostir overnight at room temperature. 35% sodium hydroxide was added andthe product was extracted with ethyl acetate. The organic phase wasseparated, washed with brine, dried over Na₂SO₄ and evaporated todryness in vacuo. The crude was purified by flash chromatography(dichloromethane/methanol 95:5) to give the title compound as a red oil(406 mg, 56%).

HRMS (ESI+): calcd. for C₁₅H₂₅N₂O₃ [M+H]⁺ 281.1860: found 281.1867.

Operating in an analogous way, but employing suitably substitutedstarting material (XIII), the following compounds were obtained:

Benzyl-furan-2-ylmethyl-amine (XVI)

HRMS (ESI+): calcd. for C₁₂H₁₄NO [M+H]⁺ 188.1070; found 188.1075.

Furan-2-ylmethyl-phenethyl-amine (XVI)

HRMS (ESI+): calcd. for C₁₃H₁₆NO [M+H]⁺ 202.1226; found 202.1230.

[2-(3,4-Dihydro-1H-isoquinolin-2-yl)-ethyl]-furan-2-ylmethyl-amine (XVI)

HRMS (ESI+): calcd. for C₁₆H₂₁N₂O [M+H]⁺ 257.1648; found 257.1642.

Furan-2-ylmethyl-(2-piperidin-1-yl-ethyl)-amine (XVI)

HRMS (ESI+): calcd. for C₁₂H₂₁N₂O [M+H]⁺ 209.1648; found 209.1650.

Furan-2-ylmethyl-(2-morpholin-4-yl-ethyl)-amine (XVI)

HRMS (ESI+): calcd. for C₁₁H₁₉N₂O₂ [M+H]⁺ 211.1441; found 211.1446.

Furan-2-ylmethyl-(3-morpholin-4-yl-propyl)-amine (XVI)

HRMS (ESI+): calcd. for C₁₂H₂₁N₂O₂ [M+H]⁺ 225.1598; found 225.1590.

[2-(3,4-Dihydro-2H-quinolin-1-yl)-ethyl]-furan-2-ylmethyl-amine (XVI)

HRMS (ESI+): calcd. for C₁₆H₂₁N₂O [M+H]⁺ 257.1648; found 257.1652.

Furan-2-ylmethyl-(3-phenyl-propyl)-amine (XVI)

HRMS (ESI+): calcd. for C₁₄H₁₈NO [M+H]⁺ 216.1383; found 216.1387.

Furan-2-ylmethyl-(2-pyridin-2-yl-ethyl)-amine (XVI)

HRMS (ESI+): calcd. for C₁₂H₁₅N₂O [M+H]⁺ 203.1179; found 203.1181.

[3-(3,4-Dihydro-1H-isoquinolin-2-yl)-propyl]-furan-2-ylmethyl-amine(XVI)

HRMS (ESI+): calcd. for C₁₇H₂₃N₂O [M+H]⁺ 271.1805; found 271.1799.

[3-(3,4-Dihydro-2H-quinolin-yl)-propyl]-furan-2-ylmethyl-amine (XVI)

HRMS (ESI+): calcd. for C₁₃H₂₃N₂O [M+H]⁺ 271.1805; found 271.1811.

Furan-2-ylmethyl-[3-(4-methyl-piperazin-1-yl)-propyl]-amine (XVI)

HRMS (ESI+): calcd. for C₁₃H₂₄N₃O [M+H]⁺ 238.1914; found 238.1912.

Furan-2-ylmethyl-[3-(4-phenyl-piperazin-1-yl)-propyl]-amine (XVI)

HRMS (ESI+): calcd. for C₁₈H₂₃N₃O [M+H]⁺ 300.2070; found 300.2077.

Furan-2-ylmethyl-(3-piperidin-1-yl-propyl)-amine (XVI)

HRMS (ESI+): calcd. for C₁₃H₂₃N₂O [M+H]⁺ 223.1805; found 223.1802.

(3-[1,4′]Bipiperidinyl-1′-yl-propyl)-furan-2-ylmethyl-amine (XVI)

HRMS (ESI+): calcd. for C₁₈H₃₂N₃O [M+H]⁺ 306.2540; found 306.2544.

[3-(2,6-Dimethyl-piperidin-1-yl)-propyl]-furan-2-ylmethyl-amine (XVI)

HRMS (ESI+): calcd. for C₁₅H₂₇N₂O [M+H]⁺ 251.2118; found 251.2120.

Furan-2-ylmethyl-[1-(tetrahydro-pyran-4-yl)-piperidin-4-yl]-amine (XVI)

HRMS (ESI+): calcd. for C₁₅H₂₅N₂O₂ [M+H]⁺ 265.1911; found 265.1919.

(1-Benzyl-piperidin-4-yl)-furan-2-ylmethyl-amine (XVI)

HRMS (ESI+): calcd. for C₁₇H₂₃N₂O [M+H]⁺ 271.1805; found 271.1807.

[2-(1-Benzyl-piperidin-4-yl)-ethyl]furan-2-ylmethyl-amine (XVI)

HRMS (ESI+): calcd. for C₁₉H₂₇N₂O [M+H]⁺ 299.2118; found 299.21222.

[3-(4-Benzyl-piperidin-1-yl)-propyl]-furan-2-ylmethyl-amine (XVI)

HRMS (ESI+): calcd. for C₂₀H₂₉N₂O [M+H]⁺ 313.2274; found 313.2280.

(1-Cyclohexyl-piperidin-4-yl)-furan-2-ylmethyl-amine (XVI)

An equimolar solution of furan-2-carbaldehyde (XV) (1.3 g, 13.5 mmol)and 1-cyclohexyl-piperidin-4-ylamine (XIII) (2.46 g, 13.5 mmol) intoluene (140 mL) was heated to relux for 8 h by employing a Dean-Starkapparatus. The reaction mixture was concentrated under vacuum and rinsedwith ethanol (50 mL). Sodium triacetoxyborohydride (3.8 g, 17.93 mmol)was added and the mixture was left overnight at room temperature. Thenit was basified with aqueous ammonia (8%) and the aqueous layer wasseparated and extracted with diethyl ether. The organic phase was driedover anhydrous sodium sulfate and concentrated under reduced pressure togive the title compound as a yellow oil employed in the following stepwithout any further purification.

HRMS (ESI+): calcd. for C₁₆H₂₇N₂O [M+H]⁺ 263.2118; found 2632120.

Step n

3-(1-Tert-butoxycarbonyl-piperidin-4-yl)-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5]dec-8-ene-6-carboxylicacid (XVII) [n=0: R1=piperidin-4-yl; X=tert-butoxycarbonyl]

To a solution of 4-[(furan-2-ylmethyl)-amino]-piperidine-1-carboxylicacid tert-butyl ester (XVI) (5.6 g, 21 mmol) in toluene (300 mL) maleicanhydride (2.1 g, 21 mmol) was added. The reaction mixture was refluxedfor 6 h and stirred overnight at room temperature. The precipitate solidobtained was filtered, washed with diethyl ether and dried to give thedesired compound (6.5 g, 82%) as a white solid.

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.40 (s, 9H), 1.40-1.63 (m, 4H), 2.45(d, J=9.3 Hz, 1H), 2.75 (br. s., 2H), 2.76 (d, J=9.3 Hz, 1H), 3.59 (d,J=11.6 Hz, 1H), 3.88 (d, J=11.60 Hz, 1H), 3.90 (m, 1H), 3.96-4.06 (m,2H), 4.95 (d, J=1.6 Hz, 1H), 6.42 (dd, J=5.6, 1.7 Hz, 1H), 6.55 (d,J=5.6 Hz, 1H), 12.03 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₉H₂₇N₂O₆ [M+H]⁺ 379.1864; found 379.1876.

Operating in an analogous way, but employing suitably substitutedstarting material (XVI) the following compounds were obtained:

3-Benzyl-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₁₆H₁₆NO₄ [M+H]⁺ 286.1074; found 286.1078.

4-Oxo-3-phenethyl-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₁₇H₁₈NO₄ [M+H]⁺ 300.1230; found 300.1237.

3-[2-(3,4-Dihydro-1H-isoquinolin-2-yl)-ethyl]-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₂₀H₂₃N₂O₄ [M+H]⁺ 355.1652: found 355.1657.

4-Oxo-3-(2-piperidin-1-yl-ethyl)-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₁₆H₂₃N₂O₄ [M+H]⁺ 307.1652; found 307.1660.

3-(2-Morpholin-4-yl-ethyl)-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₁₅H₂₁N₂O₅ [M+H]⁺ 309.1445: found 309.1446.

3-(3-Morpholin-4-yl-propyl)-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₁₆H₂₃N₂O₅ [M+H]⁺ 323.1601; found 323.1609.

3-[2-(3,4-Dihydro-2H-quinolin-1-yl)-ethyl]-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₂₀H₂₃N₂O₄ [M+H]⁺ 355.1652; found 355.1660.

4-Oxo-3-(3-phenyl-propyl)-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₁₈H₂₀NO₄ [M+H]⁺ 314.1387; found 314.1392.

4-oxo-3-(2-pyridin-2-yl-ethyl)-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₁₆H₁₇N₂O₄ [M+H]⁺ 301.1183; found 301.1179.

3-[3-(3,4-Dihydro-1H-isoquinolin-2-yl)-propyl]4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₂₁H₂₅N₂O₄ [M+H]⁺ 369.1809; found 369.1811.

3-[3-(3,4-Dihydro-2H-quinolin-1-yl)-propyl]-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₂₁H₂₅N₂O₄ [M+H]⁺ 369.1809; found 369.1801.

3-[3-(4-Methyl-piperazin-1-yl)-propyl]-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₁₇H₂₆N₃O₄ [M+H]⁺ 336.1918; found 336.1920.

4-Oxo-3-[3-(4-phenyl-piperazin-1-yl)-propyl]-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₂₂H₂₈N₃O₄ [M+H]⁺ 398.2074; found 398.2079.

4-Oxo-3-(3-piperidin-1-yl-propyl)-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₁₇H₂₅N₂O₄ [M+H]⁺ 321.1809; found 321.1812.

3-(3-[1,4′]Bipiperidinyl-1′-yl-propyl)-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₂₂H₃₄N₃O₄ [M+H]⁺ 404.2544; found 404.2540.

3-[3-(2,6-Dimethyl-piperidin-1-yl)-propyl]-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₁₉H₂₉N₂O₄ [M+H]⁺ 349.2122; found 349.2119.

4-Oxo-3-[1-(tetrahydro-pyran-4-yl)-piperidin-4-yl]-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₁₉H₂₇N₂O₅ [M+H]⁺ 363.1914; found 363.1920.

3-(1-Benzyl-piperidin-4-yl)-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₂₁H₂₅N₂O₄ [M+H]⁺ 369.1809: found 369.1799.

3-[2-(1-Benzyl-piperidin-4-yl)-ethyl]-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₂₃H₂₉N₂O₄ [M+H]⁺ 397.2122; found 397.2127.

3-[3-(4-Benzyl-piperidin-1-yl)-propyl]-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

HRMS (ESI+): calcd. for C₂₄H₃₁N₂O₄ [M+H]⁺ 4112278: found 411.2283.

3-(1-Cyclohexyl-piperidin-4-yl)-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5*]dec-8-ene-6-carboxylicAcid (XVII)

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 11.98 (br.s., 1H), 6.58 (d, J=5.6 Hz,1H), 6.44 (dd, J=5.6, 1.6 Hz, 1H), 4.97 (d, J=1.6 Hz, 1H), 4.00-4.11 (m,1H), 3.96 (d, J=11.0 Hz, 1H), 3.55 (d, J=11.0 Hz 1H), 3.38-3.48 (m, 2H),3.04-32 (m, 3H), 2.79 (d, J=9.1 Hz, 1H), 2.48 (d, J=9.1 Hz, 1H),1.55-2.01 (m, 8H), 1.04-1.44 (m, 6H).

HRMS (ESI+): calcd. for C₂₀H₂₉N₂O₄ [M+H]+ 3612122; found 361.2129.

Step o

3-Oxo-2-piperidin-4-yl-2,3-dihydro-1H-isoindole-4-carboxylic AcidHydrochloride (XIX) [n=0; R1=piperidin-4-yl]

3-(1-Tert-butoxycarbonyl-piperidin-4-yl)-4-oxo-10-oxa-3-aza-tricyclo[5.2.1.0*1,5′]dec-8-ene-6-carboxylicAcid (XVII) (6.35 g, 16.8 mmol) was dissolved in 37% hydrochloric acid(80 mL) and the resulted solution was refluxed for 3 h. The solvent wasremoved under reduced pressure and the residue was diluted with methanoland decanted to obtain the desired product (XIX) as a white solid (4.06g, 82%).

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.95-2.12 (m, 4H), 3.01-3.18 (m, 2H),3.36-3.45 (m, 2H), 4.36-4.46 (m, 1H), 4.72 (s, 2H), 7.85 (dd, J=7.7, 7.5Hz, 1H), 7.95 (dd, J=7.5, 0.8 Hz, 1H), 8.17 (dd, J=7.7, 0.8 Hz, 1H),8.53 (br. s., 1H), 8.79 (br. s., 1H), 15.86 (s, 1H).

HRMS (ESI+): calcd. for C₁₄H₁₇N₂O₃ [M+H]⁺ 261.1234; found 261.1222.

Operating in an analogous way, but employing suitably substitutedstarting material (XVII) the following compounds were obtained:

2-Benzyl-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic Acid (XVIII)

HRMS (ESI+): calcd. for C₁₆H₁₄NO₃ [M+H]⁺ 268.0968; found 268.0972.

3-Oxo-2-phenethyl-2,3-dihydro-1H-isoindole-4-carboxylic Acid (XVIII)

HRMS (ESI+): calcd. for C₁₇H₁₆NO₃ [M+H]⁺ 282.1125; found 282.1131.

2-[2-(3,4-Dihydro-1H-isoquinolin-2-yl)-ethyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₂₀H₂₁N₂O₃ [M+H]⁺ 337.1547; found 337.1541.

3-Oxo-2-(2-piperidin-1-yl-ethyl)-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₁₆H₂₁N₂O₃ [M+H]⁺ 288.1547: found 288.1552.

2-(2-Morpholin-4-yl-ethyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₁₅H₁₉N₂O₄ [M+H]⁺ 291.1339; found 291.1335.

2-(3-Morpholin-4-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₁₆H₂₁N₂O₃ [M+H]⁺ 305.1496; found 305.1492.

2-[2-(3,4-Dihydro-2H-quinolin-1-yl)-ethyl]3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₂₀H₂₁N₂O₃ [M+H]⁺ 337.1547; found 337.1549.

3-Oxo-2-(3-phenyl-propyl)-2,3-dihydro-1H-isoindole-4-carboxylic Acid(XVIII)

HRMS (ESI+): calcd. for C₁₈H₁₈NO₃ [M+H]⁺ 296.1281; found 296.1290.

3-Oxo-2-(2-pyridin-2-yl-ethyl)-2,3-dihydro-1H-isoindole-4-carboxylicacid(XVIII)

HRMS (ESI+): calcd. for C₁₆H₁₅N₂O₃ [M+H]⁺ 283.1077; found 283.1080.

2-[3-(3,4-Dihydro-1H-isoquinolin-2-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₂₁H₂₃N₂O₃ [M+H]⁺ 351.1703; found 351.1706.

2-[3-(3,4-Dihydro-2H-quinolin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₂₁H₂₃N₂O₃ [M+H]⁺ 351.1703; found 351.1699.

2-[3-(4-Methyl-piperazin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₁₁H₂₄N₃O₃ [M+H]⁺ 318.1812; found 318.1820.

3-Oxo-2-[3-(4-phenyl-piperazin-1-yl)-propyl]-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₂₂H₂₆N₃O₃ [M+H]⁺ 380.1969; found 380.1971.

3-Oxo-2-(3-piperidin-1-yl-propyl)-2,3-dihydro-1H-isoindolin-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₁₇H₂₃N₂O₃ [M+H]⁺ 303.1703; found 303.1702.

2-(3-[1,4′]Bipiperidinyl-1′-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₂₂H₃₂N₃O₃ [M+H]⁺ 3862438: found 386.2442.

2-[3-(2,6-Dimethyl-piperidin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₁₉H₂₇N₂O₃ [M+H]⁺ 331.2016; found 331.2011.

3-Oxo-2-[1-(tetrahydro-pyran-4-yl)-piperidin-4-yl]-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₁₉H₂₅N₂O₄ [M+H]⁺ 345.1809; found 345.1816.

2-(1-Benzyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₂₁H₂₃N₂O₃ [M+H]⁺ 351.1703; found 351.1708.

2-[2-(1-Benzyl-piperidin-4-yl)-ethyl]3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₂₃H₂₇N₂O₃ [M+H]⁺ 379.2016: found 379.2020.

2-[3-(4-Benzyl-piperidin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₂₄H₂₉N₂O₃ [M+H]⁺ 393.2173; found 393.2177.

2-(1-Cyclohexyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII)

HRMS (ESI+): calcd. for C₂₄H₂₉N₂O₃ [M+H]⁺ 343.2016; found 343.2019.

Step g

2-(1-Tert-butoxycarbonyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII) [n=0; R1=piperidin-4-yl; X=tert-butoxycarbonyl]

To a solution of3-oxo-2-piperidin-4-yl-2,3-dihydro-1H-isoindole-4-carboxylic Acid (3.9g, 13.2 mmol) in pyridine (15 mL) potassium carbonate (3.6 g, 26.5 mmol)and methanol (40 mL) were successively added. Then di-tert-butyldicarbonate (3.16 g, 14.5 mmol) was added and the reaction mixture wasstirred at room temperature for 4 h until HPLC analysis revealed thedisappearance of the starting material. The solvent was removed underreduced pressure and the residue was dissolved in dichloromethane. Thesolution was washed twice with 5% potassium hydrogen sulfate and theorganic phase was dried over Na₂SO₄ and concentrated in vacuo. Theobtained crude wad diluted with diethyl ether and decanted to obtain thetitle compound (3.7 g, 78%) as a white solid.

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.42 (s, 9H), 1.04-1.74 (m, 2H),1.80-1.88 (m, 2H), 2.89 (br. s., 2H), 4.04-4.12 (m, 2H), 4.23-4.32 (m,1H), 4.73 (s, 2H), 7.83 (dd, J=7.5, 0.8 Hz, 1H), 7.91 (dd, J=7.5, 0.8Hz, 1H), 8.17 (dd, J=7.7, 0.8 Hz, 1H), 16.03 (br. s., 1H).

Step p

4-(7-Carbamoyl-1-oxo-1,3-dihydro-isoindol-2-yl)-piperidine-1-carboxylicacid tert-butyl ester (XX) [n=0; R1=piperidin-4-yl;X=tert-butoxycarbonyl]

Method A: to a solution of2-(1-tert-butoxycarbonyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII) (3.7 g, 10.3 mmol) in N,N-dimethylformamide (60 mL)hydroxybenzotriazole ammonium salt (3.15 g, 20.7 mmol),1-ethyl-3-(3′-dimethylamino)carbodiimide hydrochloric acid salt (3.34 g,20.7 mmol) and diisopropylethylamine (5.3 mL, 30.9 mmol) were added. Thereaction mixture was stirred at room temperature overnight. The solventwas removed under reduced pressure and the residue was dissolved inethyl acetate. The solution was washed twice with saturated sodiumcarbonate aqueous solution, and the organic phase was dried overanhydrous sodium sulfate and concentrated in vacuo. The crude waspurified by lash chromatography (dichloromethane/methanol 97:3) toafford the title compound (2.74 g, 74%) as a white solid.

Method B: a solution of2-(1-tert-butoxycarbonyl-piperidin-4-yl)-2,3-dihydro-1H-isoindole-4-carboxylicAcid (XVIII) (5.5 g, 15.3 mmol) and carbonyldiimidazole (3.7 g, 22.8mmol) in dry tetrahydrofuran (80 mL) was stirred at room temperature for4 h. Then concentrated aqueous ammonia (25 mL) was added and thereaction mixture was left at room temperature until the disappearance ofthe starting material (3 h). The solvent was evaporated under reducedpressure and the resulting crude primary amide (1.1 g, 20%) was employedwithout any further purification.

HRMS (ESI+): calcd. for C₁₉H₂₆N₃O₄ [M+H]⁺ 360.1918; found 360.1921.

Operating according to method A, but employing suitably substitutedstarting material the following compounds were obtained:

2-benzyl-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylic Acid Amide (I), cpd1

[R═H; n=1; R1=phenyl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.72-1.88 (m, 4H), 2.04-2.13 (m, 2H),2.88-2.96 (m, 2H), 3.51 (s, 2H), 4.00-4.11 (m, 1H), 4.56 (s, 2H),7.20-7.30 (m, 1H), 7.31-7.37 (m, 4H), 7.66 (br. s., 1H), 7.71 (dd,J=7.6, 7.4 Hz, 1H), 7.76 (dd, J=7.6, 1.5 Hz, 1H), 8.20 (dd, J=7.4. 1.5Hz, 1H), 10.72 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₆H₁₅N₂O₂ [M+H]+ 267.1128; found 267.1120.

3-oxo-2-phenethyl-2,3-dihydro-1H-isoindole-4-carboxylic Acid Amide (I),cpd 2

[R═H; n=2; R1=phenyl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 2.97 (t, J=7.6 Hz, 2H), 3.82 (t, J=7.6Hz, 2H), 4.49 (s, 2H), 7.17-7.24 (m, 1H), 7.24-7.32 (m, 4H), 7.66 (br.s., 1H), 7.70 (dd, J=7.5, 7.3 Hz, 1H), 7.74 (dd, J=7.5, 1.5 Hz, 1H),8.19 (dd, J=7.3, 1.5 Hz, 1H), 10.68 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₇H₁₅N₂O₂ [M+H]⁺ 281.1285; found 281.1295.

2-[2-(3,4-dihydro-1H-isoquinolin-2-yl)-ethyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 3

[R═H; n=2; R1=3,4-dihydro-1H-isoquinolin-2-yl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 2.73-2.84 (m, 6H), 3.65 (s, 2H), 3.81(t, J=6.2 Hz, 2H), 4.65 (s, 2H), 7.00-7.12 (m, 4H), 7.66 (br. s., 1H),7.69 (dd, J=7.6, 7.7 Hz, 1H), 7.76 (dd, J=7.6, 1.2 Hz, 1H), 8.19 (dd,J=7.7, 1.2 Hz, 1H), 10.75 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₀H₂₃N₃O₂ [M+H]⁺ 336.1707; found 336.1722.

3-oxo-2-(2-piperidin-1-yl-ethyl)-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 4

[R═H; n=2; R1=piperidin-1-yl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.33-1.40 (m, 2H), 1.43-1.50 (m, 4H),2.35-2.43 (m, 4H), 2.54 (t, J=6.3 Hz, 2H), 3.68 (t, J=6.3 Hz, 2H), 4.63(s, 2H), 7.66 (br. s., 1H), 7.72 (dd, J=7.7, 7.4 Hz, 1H), 7.78 (dd,J=7.4, 1.2 Hz, 1H), 8.20 (dd, J=7.7, 1.2 Hz, 1H), 10.75 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₆H₂₂N₃O₂ [M+H]⁺ 288.1707; found 288.1712.

2-(2-morpholin-4-yl-ethyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 5

[R═H; n=2; R1=morpholin-4-yl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 2.41-2.46 (m, 4H), 2.59 (t, J=6.3 Hz,2H), 3.52-3.57 (m, 4H), 3.71 (t, J=6.3 Hz, 2H), 4.64 (s, 2H), 7.66 (br.s., 1H), 7.72 (dd. J=7.7, 7.6 Hz, 1H), 7.78 (dd, J=7.6, 1.3 Hz, 1H),8.20 (dd, J=7.7, 1.3 Hz, 1H), 10.73 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₅H₂₀N₃O₃ [M+H]⁺ 290.1499; found 290.1507.

2-(3-morpholin-4-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 6

[R═H; n=3; R1=morpholin-4-yl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.80 (quintet, J=7.1 Hz, 2H),2.28-2.38 (m, 6H), 3.47-3.54 (m, 4H), 3.61 (t, J=7.1 Hz, 2H), 4.58 (s,2H), 7.65 (br. s., 1H), 7.71 (dd, J=7.6, 7.4 Hz, 1H), 7.77 (dd, J=7.4,1.2 Hz, 1H), 8.20 (dd, J=7.6, 1.2 Hz, 1H), 10.76 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₈H₂₂N₃O₃ [M+H]⁺ 304.1656; found 304.1664.

2-[2-(3,4-dihydro-2H-quinolin-1-yl)-ethyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 7

[R═H; n=2; R1=3,4-dihydro-2H-quinolin-1-yl: m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.79-1.89 (m, 2H), 2.64-2.70 (m, 2H),3.27-3.31 (m, 2H), 3.56 (t, J=7.1 Hz, 2H), 3.76 (t, J=7.1 Hz, 2H), 4.65(s, 2H), 6.44-6.49 (m, 1H), 6.70-6.75 (m, 1H), 6.85-6.89 (m, 1H),6.92-6.97 (m, 1H), 7.69 (br. s., 1H), 7.72 (dd, J=7.6, 7.6 Hz, 1H), 7.77(dd, J=7.6, 1.3 Hz 1H), 820 (dd, J=7.6, 1.3 Hz, 1H), 10.68 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₀H₂₂N₃O₂ [M+H]⁺ 336.1707: found 336.1692.

3-oxo-2-(3-phenyl-propyl)-2,3-dihydro-1H-isoindole-4-carboxylic AcidAmide (I), cpd 17

[R═H; n=3; R1=phenyl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.97 (quintet, J=7.9 Hz, 2H), 2.64 (t,J=7.9 Hz 2H), 3.61 (t, J=7. 9 Hz, 2H), 4.59 (s, 2H), 7.15-7.20 (m, 1H),723-7.31 (m, 4H), 7.67 (br. s., 1H), 7.72 (dd, J=7.6, 7.4 Hz, 1H), 7.77(dd, J=7.6, 1.5 Hz, 1H), 8.21 (dd, J=7.4, 1.5 Hz, 1H), 10.74 (br. s.,1H).

HRMS (ESI+): calcd. for C₁₈H₁₉N₂O₂ [M+H]⁺ 295.1441; found 295.1433.

3-oxo-2-(2-pyridin-2-yl-ethyl)-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 18

[R═H; n=2; R1=pyrid-2-yl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 3.12 (t, J=7.3 Hz, 2H), 3.96 (t, J=7.3Hz, 2H), 4.52 (s, 2H), 7.23 (ddd, J=7.5, 4.9, 12 Hz, 1H), 7.32 (ddd,J=7.8, 1.2, 0.8 Hz, 1H), 7.65 (br. s., 1H), 7.71 (m, 1H), 7.70 (dd,J=7.6, 7.4 Hz, 1H), 7.75 (dd, J=7.6, 1.3 Hz, 1H), 8.19 (dd, J=7.4, 1.3Hz, 1H), 8.48 (ddd, J=4.9, 1.8, 0.8 Hz, 1H), 10.66 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₆H₁₆N₃O₂ [M+H]⁺ 282.1237; found 282.1243.

2-[3-(3,4-dihydro-1H-isoquinolin-2-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 19

[R═H; n=3; R1=3,4-dihydro-1H-isoquinolin-2-yl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.92 (quintet, J=7.3 Hz, 2H), 2.52 (t,J=7.3 Hz, 2H), 2.64-2.70 (m, 2H), 2.76-2.82 (m, 2H), 3.57 (s, 2H), 3.64(t, J=7.3 Hz, 2H), 4.60 (s, 2H), 7.00-7.70 (m, 4H), 7.66 (br. s., 1H),7.70 (dd, J=7.6, 7.4 Hz, 1H), 7.75 (dd, J=7.4, 1.3 Hz, 1H), 8.19 (dd,J=7.6, 1.3 Hz, 1H), 10.76 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₁H₂₄N₃O₂ [M+H]⁺ 350.1863; found 350.1866.

2-[3-(3,4-dihydro-2H-quinolin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 20

[R═H; n=3; R1=3,4-dihydro-2H-quinolin-1-yl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.80-1.87 (m, 2H), 1.90 (quintet J=72Hz, 2H), 2.65 (t, J=72 Hz, 2H), 3.22-3.26 (m, 2H), 327-3.30 (moverlapped by water signal, 2H), 3.64 (t J=72 Hz, 2H), 4.59 (s, 2H),6.42-6.47 (m, 1H), 6.54-6.58 (m, 1H), 6.83-6.87 (m, 1H), 6.89-6.94 (m,1H), 7.67 (br. s., 1H), 7.72 (dd, J=7.6, 7.6 Hz, 1H), 7.77 (dd, J=7.6,1.3 Hz, 1H), 8.20 (dd. J=7.6. 1.3 Hz, 1H), 10.72 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₁H₂₄N₃O₂ [M+H]⁺ 350.1863; found 350.1868.

2-[3-(4-methyl-piperazin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 21

[R═H; n=3; R1=4-methyl-piperazin-1-yl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.80 (quintet, J=7.2 Hz, 2H), 2.11 (s,3H), 2.15-2.43 (br. s., 8H), 2.33 (t, J=72 Hz, 2H), 3.60 (t, J=72 Hz,2H), 4.58 (s, 2H), 7.66 (br. s., 1H), 7.72 (dd, J=7.6, 7.4 Hz, 1H), 7.77(dd, J=7.6, 1.3 Hz, 1H), 821 (dd, J=7.4, 1.3 Hz, 1H), 10.79 (br. s.,1H).

HRMS (ESI+): calcd. for C₁₇H₂₅N₄O₂ [M+H]⁺ 317.1972: found 317.1975.

3-oxo-2-[3-(4-phenyl-piperazin-1-yl)-propyl]-23-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 22

[R═H; n=3; R1=piperazin-1-yl; m=0; R2=4-phenyl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.85 (quintet, J=7.1 Hz, 2H), 2.39 (t,J=7.1 Hz, 2H), 3.02-3.10 (m, 4H), 3.63 (t, J=7.1 Hz, 2H), 4.60 (s, 2H),6.75 (t, J=7.3 Hz, 1H), 6.89 (d, J=7.9 Hz, 2H), 7.19 (dd, J=7.9, 7.3 Hz,2H), 7.66 (br. s., 1H), 7.70 (dd, J=7.7. 7.4 Hz, 1H), 7.76 (dd, J=7.4,1.2 Hz, 1H), 820 (dd, J=7.7, 1.2 Hz, 1H), 10.78 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₂H₂₇N₄O₂ [M+H]⁺ 379.2129; found 379.2145.

3-oxo-2-(3-piperidin-1-yl-propyl)-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide Hydrochloride (I), cpd 25

[R═H; n=3; R1=piperidin-1-yl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.29 (m, 1H), 1.50-1.73 (m, 3H),1.75-1.85 (m, 2H), 2.00-2.09 (m, 2H), 2.79-2.92 (m, 2H), 3.03-3.14 (m,2H), 3.40-3.50 (m, 2H), 3.66 (t, J=6.6 Hz, 2H), 4.59 (s, 2H), 7.71 (br.s., 1H), 7.74 (dd, J=7.6, 7.4 Hz, 1H), 7.80 (dd, J=7.4, 1.1 Hz, 1H),8.21 (dd, J=7.6, 1.1 Hz, 1H), 8.93 (br. s., 1H), 10.58 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₇H₂₄NO₂ [M+H]⁺ 302.1863; found 302.1865.

2-(3-[1,4′]bipiperidinyl-1′-yl-propyl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide Dihydrochloride (I), cpd 26

[R═H; n=3; R1=piperidin-1-yl; m=0; R2=4-piperidin-1-yl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.33-1.49 (m, 1H), 1.57-1.74 (m, 3H),1.74-1.94 (m, 4H), 1.95-2.13 (m, 2H), 2.16-2.30 (m, 2H), 2.87-3.72 (m,11H), 3.66 (t, J=6.5 Hz, 2H), 4.59 (s, 2H), 7.72 (br. s., 1H), 7.75 (dd,J=7.6, 6.7 Hz, 1H), 7.80 (d, J=6.7 Hz, 1H), 8.21 (dd, J=7.6, 1.2 Hz,1H), 9.38 (br. s., 2H), 10.58 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₂H₃₃N₄O₂ [M+H]⁺ 385.2598: found 385.2611.

2-[3-(2,6-dimethyl-piperidin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide Hydrochloride (I), cpd 27

[R═H; n=3; R1=2,6-dimethyl-piperidin-1-yl; m=0; R2=null]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.25 (d, J=6.3 Hz, 6H), 1.40-1.55 (m,3H), 1.80-1.91 (m, 2H), 1.95-2.05 (m, 2H), 3.02-3.46 (m, 4H), 3.68 (m,2H), 4.63 (s, 2H), 7.70 (br. s., 1H), 7.74 (dd, J=7.6, 7.6 Hz, 1H), 7.80(dd, J=7.6, 1.2 Hz, 1H), 8.21 (dd, J=7.6, 1.2 Hz, 1H), 8.72 (br. s.,1H), 10.58 (br. s., 1H).

HRMS (ESI+): calcd. for CH₁₉H₂₈N₃O₂ [M+H]⁺ 330.2176; found 330.2176.

3-ox-2-[1-(tetrahydro-pyran-4-yl)-piperidin-4-yl]-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 28

[R═H; n=m=0; R1=piperidin-4-yl; R2=1-(tetrahydro-pyran-4-yl)]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.38-1.50 (m, 2H), 1.65-1.72 (m, 2H),1.73-1.81 (m, 4H), 2.18-2.28 (m, 2H), 2.43-2.47 (m, 1H), 2.97-3.04 (m,2H), 3.30 (m overlapped by water signal, 2H), 3.89 (dd. J=11.1, 3.9 Hz,2H), 4.02 (m, 1H), 4.55 (s, 2H), 7.66 (br. s., 1H), 7.71 (dd, J=7.6, 7.4Hz, 1H), 7.76 (dd, J=7.4, 1.5 Hz, 1H), 8.20 (dd, J=7.6, 1.5 Hz, 1H),10.74 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₉H₂₆N₃O₃ [M+H]⁺ 344.1969; found 344.1962.

2-(1-benzyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 30

[R═H; n=0; R1=piperidin-4-yl; m=1; R2=phenyl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.70-1.88 (m, 4H), 1.99-2.13 (m, 2H),2.89-2.96 (m, 2H), 3.51 (s, 2H), 4.00-4.11 (m, 1H), 4.56 (s, 2H),720-7.30 (m, 1H), 7.30-7.36 (m, 4H), 7.66 (br. s., 1H), 7.71 (dd, J=7.6,7.4 Hz, 1H), 7.76 (dd, J=7.6, 1.5 Hz, 1H), 8.20 (dd, J=7.4, 1.5 Hz, 1H),10.72 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₁H₂₄N₃O₂ [M+H]⁺ 350.1863; found 350.1874.

2-[2-(1-benzyl-piperidin-4-yl)-ethyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide Hydrochloride (I), cpd 31

[R═H; n=2; R1=piperidin-4-yl; m=1; R2=phenyl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 129-1.41 (m, 2H), 1.43-1.54 (m, 1H),1.56-1.64 (m, 2H), 1.92-2.00 (m, 2H), 2.83-2.96 (m, 2H), 3.30 (moverlapped by water signal, 2H), 3.61 (t, J=6.8 Hz, 2H), 4.25 (d, J=5.1Hz, 2H), 4.57 (s, 2H), 7.47 (s, 5H), 7.69 (br. s., 1H), 7.72 (dd, J=7.6,7.4 Hz, 1H), 7.77 (dd, J=7.4, 1.3 Hz, 1H), 8.20 (dd, J=7.6, 1.3 Hz, 1H),9.22 (br. s., 1H), 10.68 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₁H₂₄N₃O₂ [M+H]⁺ 378.2176; found 378.2178.

2-[3-(4-benzyl-piperidin-1-yl)-propyl]-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 32

[R═H; n=3; R1=piperidin-1-yl; m=1; R2=phenyl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 0.93-1.12 (m, 2H), 1.34-1.53 (m, 3H),1.68-1.82 (m, 4H), 2.22-2.33 (m, 2H), 2.41 (d, J=6.8 Hz, 2H), 2.75-2.85(m, 2H), 3.59 (t, J=6.9 Hz, 2H), 4.56 (s, 2H), 7.09-7.14 (m, 2H),7.14-7.19 (m, 1H), 7.23-7.29 (m, 2H), 7.65 (br. s., 1H), 7.72 (dd,J=7.4, 7.4 Hz, 1H), 7.77 (dd, J=7.4, 1.3 Hz, 1H), 8.21 (dd, J=7.4, 1.3Hz, 1H), 10.78 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₄H₃₀N₃O [M+H]⁺ 392.2333; found 392.2346.

Step i′

3-Oxo-2-piperidin-4-yl-2,3-dihydro-1H-isoindole-4-carboxylic Acid AmideHydrochloride (XXI)

[n=0; R1=piperidin-4-yl]

A solution of4-(7-carbamoyl-1-ox-1,3-dihydro-isoindol-2-yl)-piperidine-1-carboxylicacid tert-butyl ester (XX) (2.7 g, 7.5 mmol) in 4M hydrochloric acid indioxane (18 mL, 75 mmol) was stirred at 50° C. for 2 h until HPLCanalysis revealed the disappearance of the starting material. Thesolvent was removed under reduced pressure and the product was dissolvedin diethyl ether and filtered to obtain the title compound (2.09 g, 95%)as its hydrochloride.

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.93-2.09 (m, 4H), 3.03-3.17 (m, 2H),3.35-3.48 (m overlapped by water signal, 2H), 4.32-4.45 (m, 1H), 4.56(s, 2H), 7.71 (br. s., 1H), 7.75 (dd, J=7.5, 7.5 Hz, 1H), 7.82 (dd,J=7.5, 1.1 Hz 1H), 8.21 (dd, J=7.5, 1.1 Hz, 1H), 8.59 (br.s., 1H), 8.82(br. s., 1H), 10.58 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₄H₁₈N₃O₂ [M+H]⁺ 260.1394; found 260.1398.

Step l′

2-(1-cyclohexyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 11

[R═H; n=m=0; R1=piperidin-4-yl; R2=1-cyclohexyl]

Method A: to a suspension of3-oxo-2-piperidin-4-yl-2,3-dihydro-1H-isoindole-4-carboxylic acid amidehydrochloride (56 mg, 0.19 mmol) in dichloromethane (2 mL),cyclohexanone (XIV) (27.5 mg, 028 mmol), sodium acetate (32 mg, 0.38mmol) and methanol (0.3 mL) were added. The resultant solution wasstirred at room temperature for 5 h. Then sodium cyanoborohydride (13mg, 0.21 mmol) was added and the mixture was stirred overnight Solventswere removed under reduced pressure and the residue was dissolved indichloromethane and washed twice with water.

The organic phase was dried over Na₂SO₄ and concentrated in vacuo andthe residue was purified by flash chromatography(dichloromethane/methanol 95:5) to give 27 mg (40%) of2-(1-cyclohexyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicacid amide.

Method B: to a solution of2-piperidin-4-yl-2,3-dihydro-1H-isoindole-4-carboxylic acid amidehydrochloride (4.4 g, 14.8 mmol) and cyclohexanone (2.2 g, 22.45 mmol)in N,N-dimethylformamide (100 mL), glacial acetic Acid (4.5 mL) andtetramethylammonium triacetoxyborohydride (11.8 g, 44.85 mmol) wereadded. The resulting solution was allowed to stir overnight at roomtemperature.

The solvent was then evaporated under reduced pressure and the resultantresidue was diluted with aqueous 8% ammonia solution and extracted withethyl acetate. The organic phase was dried with anhydrous sodium sulfateand concentrated. The crude was purified by flash chromatography(dichloromethane/methanol 95:5) and subsequently dissolved in a smallamount of methanol and precipitated with diethyl ether. The precipitatewas filtered and washed with diethyl ether to give 1.77 g of the desiredproduct as a white solid (35%).

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.00-1.14 (m, 1H), 1.14-1.32 (m, 4H),1.55-1.62 (m, 1H), 1.70-1.80 (m, 8H), 225-2.37 (m, 3H), 2.88-2.98 (m,2H), 3.95-4.06 (m, 1H), 4.55 (s, 2H), 7.66 (br. s., 1H), 7.71 (dd,J=7.6, 7.6 Hz, 1H), 7.76 (dd, J=7.6, 1.5 Hz, 1H), 8.20 (dd, J=7.6, 1.5Hz, 1H), 10.74 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₀H₂₈N₃O₂ [M+H]⁺ 342.2176; found 342.2175.

Operating according to method A, but employing suitably substitutedstarting material (XIV), the following compounds were obtained:

3-oxo-2-(1-pyridin-4-ylmethyl-piperidin-4-yl)-2,3-dihyd-1H-isoindole-4-carboxylicAcid Amide (I), cpd 8

[R═H; n=0; R1=piperidin-4-yl; m=1; R2=pyrid-4-yl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.75-1.92 (m, 4H), 2.11-2.22 (m, 2H),2.88-2.95 (m, 2H), 3.56 (s, 2H), 4.02-4.14 (m, 1H), 4.58 (s, 2H),7.33-7.38 (m, 2H), 7.68 (br. s., 1H), 7.73 (dd, J=7.6, 7.6 Hz, 1H), 7.78(dd, J=7.6, 1.5 1H), 8.21 (dd, J=7.6, 1.4 Hz, 1H), 8.51-8.55 (m, 2H),10.72 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₀H₂₃N₄O₂ [M+H]⁺ 351.1816; found 351.1817.

3-oxo-2-(1-thiophen-2-ylmethyl-piperidin-4-yl)-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 9

[R═H; n=0; R1=piperidin-4-yl; m=1; R2=thiophen-2-yl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.73-1.88 (m, 4H), 2.06-2.20 (m, 2H),2.94-3.03 (m, 2H), 3.73 (s, 2H), 4.01-4.11 (m, 1H), 4.58 (s, 2H),6.96-7.00 (m, 2H), 7.42-7.46 (m, 1H), 7.67 (br. s., 1H), 7.72 (dd,J=7.6, 7.4 Hz, 1H), 7.77 (dd, J=7.6, 1.5 Hz, 1H), 8.21 (dd, J=7.4, 1.5Hz, 1H), 10.72 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₉H₂₂N₃O₂S [M+H]⁺ 356.1427; found 356.1430.

3-oxo-2-(1-pyridin-3-ylmethyl-piperidin-4-yl)-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 10

[R═H; n=0; R1=piperidin-4-yl; m=1; R2=pyrid-3-yl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.70-1.80 (m, 4H), 2.08-2.18 (m, 2H),2.87-2.96 (m, 2H), 3.55 (s, 2H), 4.01-4.12 (m, 1H), 4.56 (s, 2H), 7.37(dd, J=7.7, 4.8 Hz 1H), 7.66 (br. s., 1H), 7.71 (t, J=7.7, 7.4 Hz, 1H),7.73 (signal overlapped by others, 1H), 7.76 (dd, J=7.7, 1.3 Hz, 1H),8.20 (dd, J=7.4, 1.3 Hz, 1H), 8.48 (d, J=4.8 Hz, 1H), 8.52 (s, 1H),10.71 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₀H₂₃N₄O₂ [M+H]⁺ 351.1816; found 351.1822.

2-(1-furan-2-ylmethyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 12

[R═H; n=0; R1=piperidin-4-yl; m=1; R2=fur-2-yl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.70-1.87 (m, 4H), 2.07-2.16 (m, 2H),2.90-2.97 (m, 1H), 3.53 (s, 2H), 3.98-4.06 (m, 1H), 4.55 (s, 2H), 6.30(d, J=2.4 Hz, 1H), 6.41 (dd, J=2.4, 1.8 Hz, 1H), 7.59 (br. s., 1H), 7.66(br. s., 1H), 7.71 (dd, J=7.6, 7.4 Hz, 1H), 7.76 (dd, J=7.4, 1.3 Hz,1H), 8.19 (dd, J=7.6, 1.3 Hz, 1H), 10.71 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₉H₂₂N₃O₃ [M+H]⁺ 340.1656; found 340.1651.

3-oxo-2-(1-thiophen-3-ylmethyl-piperidin-4-yl)-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 13

[R═H; n=0; R1=piperidin-4-yl; m=1; R2=thiophen-3-yl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.72-1.90 (m, 4H), 2.00-2.12 (m, 2H),2.90-2.99 (m, 2H), 3.53 (s, 2H), 4.00-4.09 (m, 1H), 4.57 (s, 2H) 7.08(d, J=4.6 Hz, 1H), 7.33 (br. s., 1H), 7.49 (dd, J=4.6, 2.8 Hz, 1H), 7.67(br. s., 1H), 7.72 (dd, J=7.6, 7.4 Hz, 1H), 7.75 (dd, J=7.6, 1.3, 1H),8.21 (dd, J=7.4, 1.3 Hz, 1H), 10.73 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₉H₂₂N₃O₂S [M+H]⁺ 356.1427; found 356.1432.

2-(1-furan-3-ylmethyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 14

[R═H; n=0; R1=piperidin-4-yl; m=1; R2=fur-3-yl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.72-1.89 (m, 4H), 2.02-2.12 (m, 2H),2.90-3.02 (m, 2H), 3.37 (s, 2H), 4.00-4.10 (m, 1H), 4.56 (s, 2H), 6.45(s, 1H), 7.58 (s, 1H), 7.62 (s, 1H), 7.67 (br. s., 1H), 7.72 (dd, J=7.6,7.4 Hz, 1H), 7.76 (dd, J=7.4, 1.5 Hz, 1H), 8.21 (dd, J=7.6, 1.5 Hz, 1H),10.73 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₉H₂₂N₃O₃ [M+H]⁺ 340.1656; found 340.1649.

3-oxo-2-(1-pyridin-2-ylmethyl-piperidin-4-yl)-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 15

[R═H; n=0; R1=piperidin-4-yl; m=1; R2=pyrid-2-yl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.74-1.93 (m, 4H), 2.12-2.28 (m, 2H),2.91-3.00 (m, 2H), 3.65 (s, 2H), 4.02-4.13 (m, 1H), 4.58 (s, 2H), 7.28(dd, J=6.8, 4.8 Hz, 1H), 7.47 (d, J=7.8 Hz, 1H), 7.67 (br. s., 1H), 7.73(dd, J=7.4, 7.4 Hz, 1H), 7.76-7.83 (m, 2H), 8.21 (dd, J=7.4, 1.3 Hz,1H), 8.51 (d, J=4.8 Hz, 1H), 10.73 (br. s., 1H).

HRMS (ESI+): calcd. for C₂₀H₂₃N₄O₂ [M+H]⁺ 351.1816; found 351.1815.

3-oxo-2-[1-(1H-pyrrol-2-ylmethyl)-piperidin-4-yl]-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 16

[R═H; n=0; R1=piperidin-4-yl; m=1; R2=1H-pyrrol-2-yl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 1.70-1.88 (m, 4H), 1.96-2.09 (m, 2H),2.88-2.99 (m, 2H), 3.44 (s, 2H), 3.94-4.09 (m, 1H), 4.55 (s, 2H), 5.89(br. s., 1H), 5.94 (br. s., 1H), 6.65 (br. s., 1H), 7.67 (br. s., 1H),7.72 (dd, J=7.6, 7.4 Hz, 1H), 7.77 (dd, J=7.6, 1.3 Hz, 1H), 8.20 (dd,J=7.4, 1.3 Hz, 1H), 10.65 (br. s., 1H), 10.73 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₉H₂₃N₄O₂ [M+H]⁺ 339.1816; found 339.1812.

2-(1-cyclopropylmethyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicAcid Amide (I), cpd 24

[R═H; n=0; R1=piperidin-4-yl; m=1; R2=cyclopropyl]

¹H NMR (400.5 MHz, DMSO-d₆) δ ppm 0.06-0.12 (m, 2H), 0.44-0.50 (m, 2H),0.80-0.89 (m, 1H), 1.72-1.88 (m, 4H), 2.00-2.11 (m, 2H), 2.21 (d, J=6.3Hz, 2H), 3.04-3.13 (m, 2H), 3.98-4.09 (m, 1H), 4.56 (s, 2H), 7.66 (br.s., 1H), 7.72 (dd, J=7.6, 7.6 Hz, 1H), 7.77 (dd. J=7.6, 12 Hz, 1H), 820(dd, J=7.6, 1.2 Hz, 1H), 10.73 (br. s., 1H).

HRMS (ESI+): calcd. for C₁₈H₂₄N₃O₂ [M+H]⁺ 314.1863; found 314.1860.

The invention claimed is:
 1. A method for treating a disease mediated byPARP-1 protein which comprises administering to a mammal in need thereofan effective amount of a compound selected from the group consisting of:2-(1-cyclohexyl-piperidin-4-yl)-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicacid amide; and2-(1-cyclohexyl-piperidin-4-yl)-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicacid amide; or a pharmaceutically acceptable salt thereof, wherein themammal in need is a human and the disease mediated by PARP-1 protein iscancer.
 2. The method according to claim 1, wherein the cancer isselected from the group consisting of breast cancer, ovary cancer, braincancer, prostate cancer, liver cancer and pancreas cancer.
 3. The methodaccording to claim 1, wherein the compound is2-(1-cyclohexyl-piperidin-4-yl)-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicacid amide.
 4. The method according to claim 2, wherein the compound is2-(1-cyclohexyl-piperidin-4-yl)-6-fluoro-3-oxo-2,3-dihydro-1H-isoindole-4-carboxylicacid amide.